US20180183341A1 - Power supply unit - Google Patents
Power supply unit Download PDFInfo
- Publication number
- US20180183341A1 US20180183341A1 US15/583,391 US201715583391A US2018183341A1 US 20180183341 A1 US20180183341 A1 US 20180183341A1 US 201715583391 A US201715583391 A US 201715583391A US 2018183341 A1 US2018183341 A1 US 2018183341A1
- Authority
- US
- United States
- Prior art keywords
- winding
- power supply
- end portion
- primary
- transformer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/80—Details relating to power supplies, circuits boards, electrical connections
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/10—Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0016—Control circuits providing compensation of output voltage deviations using feedforward of disturbance parameters
- H02M1/0022—Control circuits providing compensation of output voltage deviations using feedforward of disturbance parameters the disturbance parameters being input voltage fluctuations
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/003—Constructional details, e.g. physical layout, assembly, wiring or busbar connections
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
- H02M3/33523—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters with galvanic isolation between input and output of both the power stage and the feedback loop
Definitions
- the present invention relates to a power supply unit.
- a power supply unit supplying a predetermined voltage is formed by using a transformer corresponding to the voltage supplied from a commercial power supply.
- a power supply unit including a primary circuit, a transformer, and a secondary circuit.
- the primary circuit is connected to an alternating-current power supply and includes a switching device.
- the transformer includes a primary winding and a secondary winding.
- the primary winding receives an alternating current in such a manner that an alternating current is induced in the secondary winding.
- the received alternating current is generated through switching using the switching device.
- the secondary circuit rectifies, for output, the alternating current induced in the secondary winding.
- the primary winding includes a first winding and a second winding. When the alternating-current power supply is a power supply of a first voltage, the first winding is connected to the second winding in parallel in the primary winding. When the alternating-current power supply is a power supply of a second voltage higher than the first voltage, the first winding is connected to the second winding in series in the primary winding.
- FIG. 1 is a schematic sectional view of an image forming apparatus
- FIG. 2A is a diagram for describing an overview of a transformer in a power supply unit to which a first exemplary embodiment is applied and which receives low-voltage alternating current;
- FIG. 2B is a diagram for describing an overview of a transformer in a power supply unit to which the first exemplary embodiment is applied and which receives high-voltage alternating current;
- FIG. 3A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which the first exemplary embodiment is applied;
- FIG. 3B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the first exemplary embodiment is applied;
- FIG. 4A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a second exemplary embodiment is applied;
- FIG. 4B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the second exemplary embodiment is applied;
- FIG. 5A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a third exemplary embodiment is applied;
- FIG. 5B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the third exemplary embodiment is applied;
- FIG. 6A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a fourth exemplary embodiment is applied;
- FIG. 6B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the fourth exemplary embodiment is applied;
- FIG. 7A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a fifth exemplary embodiment is applied.
- FIG. 7B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the fifth exemplary embodiment is applied.
- FIG. 1 is a schematic sectional view of an image forming apparatus 1 .
- the illustrated image forming apparatus 1 is an electrophotographic color printer that prints an image on the basis of image data.
- the image forming apparatus 1 includes, within a body case 90 , a sheet accommodating unit 40 in which sheets Q are accommodated, an image forming unit 10 that forms an image on a sheet Q, and a conveying unit 50 that conveys a sheet Q from the sheet accommodating unit 40 through the image forming unit 10 to a sheet eject portion 96 of the body case 90 .
- the image forming apparatus 1 also includes a controller 31 that controls the entire operations of the image forming apparatus 1 , a communication unit 32 that communicates, for example, with a personal computer (PC) 3 , an image reading apparatus (scanner) 4 , and the like and that receives image data, and an image processor 33 that performs image processing on image data received by the communication unit 32 .
- PC personal computer
- scanner image reading apparatus
- the image forming apparatus 1 further includes an image-formation power supply unit 80 for supplying high-voltage power to the image forming unit 10 .
- the image forming apparatus 1 furthermore includes a power supply unit 70 that receives an alternating current from a commercial power supply and that supplies direct-current power to the image-formation power supply unit 80 , the controller 31 , the communication unit 32 , and the image processor 33 .
- the power supply unit 70 serves as an exemplary power supply unit.
- the sheet accommodating unit 40 contains the sheets Q.
- the conveying unit 50 includes a transport path 51 for a sheet Q and conveying rollers 52 .
- the transport path 51 extends from the sheet accommodating unit 40 through the image forming unit 10 to the sheet eject portion 96 .
- the conveying rollers 52 convey a sheet Q along the transport path 51 .
- the conveying unit 50 conveys a sheet Q in the arrow C direction.
- the image forming unit 10 includes four image forming units 11 Y, 11 M, 11 C, and 11 K that are disposed at predetermined intervals.
- image forming units 11 include a photoconductor drum 12 , a charger 13 , a light emitting diode (LED) print head 14 , a developing unit 15 , and a drum cleaner 16 .
- the photoconductor drum 12 forms an electrostatic latent image and holds a toner image.
- the charger 13 charges the surface of the photoconductor drum 12 with a predetermined potential.
- the LED print head 14 exposes the photoconductor drum 12 charged by the charger 13 , to light on the basis of image data of the corresponding color.
- the developing unit 15 develops an electrostatic latent image formed on the surface of the photoconductor drum 12 .
- the drum cleaner 16 cleans the surface of the photoconductor drum 12 after transfer.
- the four image forming units 11 Y, 11 M, 11 C, and 11 K have similar configurations except toner contained in the developing unit 15 , and the image forming unit 11 Y including the developing unit 15 containing yellow (Y) toner forms a yellow toner image.
- the image forming unit 11 M including the developing unit 15 containing magenta (M) toner forms a magenta toner image
- the image forming unit 11 C including the developing unit 15 containing cyan (C) toner forms a cyan toner image
- the image forming unit 11 K including the developing unit 15 containing black (K) toner forms a black toner image.
- the image forming unit 10 includes an intermediate transfer belt 20 and first transfer rollers 21 .
- the first transfer rollers 21 sequentially performs electrostatic transfer (first transfer) onto the intermediate transfer belt 20 , on the color toner images formed by the image forming units 11 .
- the image forming unit 10 includes a second transfer roller 22 and a fixing unit 60 .
- the second transfer roller 22 performs electrostatic transfer (second transfer) onto a sheet Q at a time, on the superimposed toner images obtained by transferring the color toner images onto the surface of the intermediate transfer belt 20 in a superimposed manner.
- the fixing unit 60 fixes the superimposed toner images that have been subjected to second transfer onto the sheet Q.
- the image forming apparatus 1 performs an image forming process through the following processes under operation control exerted by the controller 31 . That is, image data transmitted from the PC 3 or the scanner 4 is received by the communication unit 32 . After the image processor 33 performs predetermined image processing on the image data, the image data is converted into image data of each color which is transmitted to the image forming unit 11 for the corresponding color. For example, in the image forming unit 11 K that forms a black toner image, while rotating in the arrow A direction, the photoconductor drum 12 is charged at a predetermined potential by the charger 13 .
- the print head 14 scans and exposes, to light, the photoconductor drum 12 on the basis of black image data transmitted from the image processor 33 .
- an electrostatic latent image corresponding to the black image data is formed on the surface of the photoconductor drum 12 .
- the black electrostatic latent image formed on the photoconductor drum 12 is developed by the developing unit 15 , and a black toner image is formed on the photoconductor drum 12 .
- the image forming units 11 Y, 11 M, and 11 C form toner images of yellow (Y), magenta (M), and cyan (C), respectively.
- the first transfer rollers 21 are used to sequentially perform electrostatic transfer on the color toner images formed on the photoconductor drums 12 of the image forming units 11 , onto the intermediate transfer belt 20 that moves in the arrow B direction, and the superimposed toner images obtained by superimposing the color toner images are formed on the intermediate transfer belt 20 .
- the intermediate transfer belt 20 moves in the arrow B direction so that the superimposed toner images on the intermediate transfer belt 20 are conveyed to the second transfer roller 22 .
- the conveying rollers 52 of the conveying unit 50 convey a sheet Q from the sheet accommodating unit 40 in the arrow C direction along the transport path 51 .
- the superimposed toner images formed on the intermediate transfer belt 20 are subjected to electrostatic transfer at a time onto the sheet Q conveyed along the transport path 51 , due to a transfer electric field formed by the second transfer roller 22 .
- the sheet Q onto which electrostatic transfer has been performed on the superimposed toner images is conveyed to the fixing unit 60 along the transport path 51 .
- the fixing unit 60 applies heating and pressure to fix, onto the sheet Q, the superimposed toner images on the sheet Q which have been conveyed to the fixing unit 60 .
- the sheet Q on which the fixed superimposed toner images are formed is conveyed in the arrow C direction along the transport path 51 , and is ejected from the sheet eject portion 96 of the body case 90 . Then, the sheet Q is loaded on the sheet loading unit 95 on which sheets are to be put.
- the process of the image forming apparatus 1 printing an image on a sheet Q is repeatedly performed in cycles, the number of which corresponds to the number of copies.
- the power supply unit 70 receives an alternating current from a commercial power supply (alternating-current power supply), supplies, for example, a direct current of 24 V to the image-formation power supply unit 80 , and supplies, for example, a direct current of 5 V to the controller 31 , the communication unit 32 , and the image processor 33 .
- a commercial power supply alternating-current power supply
- supplies for example, a direct current of 24 V to the image-formation power supply unit 80
- the image forming apparatus 1 includes the power supply unit 70 corresponding to the voltage of a commercial power supply from which power is received (supplied).
- the power supply unit 70 uses a switching regulator system using a switching device.
- a transformer TF is used for the voltage conversion.
- FIGS. 2A and 2B are diagrams for describing an overview of the transformer TF in the power supply unit 70 to which the first exemplary embodiment is applied.
- FIG. 2A illustrates a case in which a low-voltage alternating current is received
- FIG. 2B illustrates a case in which a high-voltage alternating current is received.
- a low-voltage system of, for example, 120 V and a high-voltage system of, for example, 240 V are illustrated.
- the relationship of winding numbers in the transformer TF is illustrated, and, in each of the lower portions, the configuration of a primary winding P is illustrated.
- a case in which a low-voltage alternating current is received is denoted as a case of a low-voltage system
- a case in which a high-voltage alternating current is received is denoted as a case of a high-voltage system.
- the winding number N P of the primary winding P of the transformer TF is 50 turns (T), and the winding number N S1 of a secondary winding S 1 is 10 T. Accordingly, 24 V is obtained from 120 V.
- the winding number N P of the primary winding P of the transformer TF is 100 T
- the winding number N S1 of the secondary winding S 1 is 10 T.
- 24 V is obtained from 240 V.
- the winding number N S1 of the secondary winding S 1 is 10 T.
- the winding number N P of the primary winding P in the case of a low-voltage system i.e., 50 T
- the winding number N P in the case of a high-voltage system i.e., 100 T. Therefore, if this configuration is used, it is not possible to commonly use the transformer TF in the low-voltage system and the high-voltage system.
- the transformer TF to which the first exemplary embodiment is applied employs a configuration in which the primary winding P is divided into two windings P 1 and P 2 , each of which has a winding number N P of 50 T.
- the winding P 1 and the winding P 2 are connected to each other in parallel.
- the winding number N P of the primary winding P is 50 T.
- the winding P 1 and the winding P 2 are connected to each other in series.
- the winding number N P of the primary winding P is 100 T.
- Each of the windings P 1 and P 2 is wound so that voltage is generated in the same direction with respect to the secondary winding S 1 .
- This configuration enables many components included in the transformer TF to be commonly used for both of a low-voltage alternating current and a high-voltage alternating current that are received by the image forming apparatus 1 . Therefore, it is not necessary to prepare different transformers TF for the image forming apparatus 1 receiving a low-voltage alternating current and the image forming apparatus 1 receiving a high-voltage alternating current, achieving simple management of components and reduction in cost.
- the inductance is equal to L 1 +L 2 in the case of series connection, and the inductance is equal to 1/(1/L 1 +1/L 2 ) in the case of parallel connection.
- the direct current resistance is equal to 1/(1/R 1 +1/R 2 ) in the case of parallel connection, and the direct current resistance is equal to R 1 +R 2 in the case of series connection.
- the inductance is equal to 2 L in the case of series connection, and is equal to L/2 in the case of parallel connection.
- the direct current resistance is equal to R/2 in the case of parallel connection, and is equal to 2 R in the case of series connection. That is, the direct current resistance obtained in the case of a low-voltage system is a quarter of the direct current resistance of a high-voltage system.
- the loss (heating value) produced due to the direct current resistance of the primary winding P is proportional to the multiplication product of the square of a current and the direct current resistance. Therefore, when the same power is to be supplied to the secondary winding S 1 (24 V side), the current in the low-voltage system that is twice the current in the high-voltage system needs to flow. However, since the direct current resistance in the low-voltage system is a quarter of the direct current resistance in the high-voltage system, the loss (heating value) is the same.
- 24 V may be obtained from the low-voltage system (120 V).
- the direct current resistance obtained in the case of a low-voltage system is equal to R and is half the direct current resistance obtained in the case of a high-voltage system.
- the loss (heating value) in the primary winding P in the low-voltage system is twice the loss in the high-voltage system.
- Table 1 describes an exemplary configuration of the transformer to which the first exemplary embodiment is applied.
- the primary winding P is divided into the two windings P 1 and P 2 .
- Table 1 describes the winding numbers N P1 and N P2 and the inductances L P1 and L P2 for the windings P 1 and P 2 .
- Table 1 describes the winding number and the inductance of the primary winding P in the low-voltage system and the winding number and the inductance in the high-voltage system, and also describes an exemplary maximum current I PMAX that flows through the primary winding P.
- the maximum current I PMAX that flows through the primary winding P in the low-voltage system is twice the maximum current I PMAX in the high-voltage system. Accordingly, as the direct current resistance is smaller, the loss (heating value) may be made smaller.
- the low-voltage system serves as an exemplary first voltage
- the high-voltage system serves as an exemplary second voltage
- the low-voltage system is an exemplary 100 V system
- the high-voltage system is an exemplary 200 V system.
- FIGS. 3A and 3B illustrate exemplary configurations of the power supply unit 70 to which the first exemplary embodiment is applied.
- FIG. 3A illustrates a low-voltage power supply unit 70
- FIG. 3B illustrates a high-voltage power supply unit 70 .
- the low-voltage system is a system for alternating current of 100 V
- the high-voltage system is a system for alternating current of 200 V. Accordingly, the low-voltage system is denoted as 100 V or a low-voltage system (100 V)
- the high-voltage system is denoted as 200 V or a high-voltage system (200 V).
- a description will be made under the assumption that the power supply unit 70 outputs a direct current of 24 V.
- the power supply unit 70 includes a power supply substrate 71 , electronic components mounted on the power supply substrate 71 , and the transformer TF mounted on the power supply substrate 71 .
- the power supply substrate 71 includes an insulated substrate formed of paper-based phenol, glass epoxy, or the like, and multiple pattern conductors M that are formed of copper foil or the like on one of the surfaces of the insulated substrate.
- the power supply substrate 71 is formed of a single-layer board having one surface on which a conductor layer such as copper foil is formed. Therefore, the power supply substrate 71 is formed of a single-layer board, and has, on one of the surfaces, the pattern conductors M formed by processing the conductor layer.
- the power supply substrate 71 may be formed, for example, of a double-sided board having conductor layers formed on both of the surfaces, or a multilayer board including multiple conductor layers.
- the size of the power supply substrate 71 of the low-voltage power supply unit 70 is the same as the size of the power supply substrate 71 of the high-voltage power supply unit 70 .
- each of the pattern conductors M is denoted as a pattern conductor Mx.
- the symbol ‘x’ indicates a number for identifying the pattern conductor. The same is true for other components.
- the electronic components are a diode bridge DB, a field-effect transistor FET, capacitors C 1 , C 2 , and C 3 , and diodes D 2 and D 3 which are connected to either one of the pattern conductors M.
- the transformer TF will be described. As described above, the transformer TF is commonly used in the low-voltage system ( FIG. 3A ) and the high-voltage system ( FIG. 3B ).
- the transformer TF is formed as an electronic component having 14 pins (pins #1 to #14).
- the 14 pins are inserted into holes disposed in the power supply substrate 71 , and each are connected to a corresponding one of the pattern conductors M.
- the transformer TF is electrically connected to pattern conductors M of the power supply substrate 71 through the pins, and is fixed to the power supply substrate 71 .
- the pins #1 to #14 of the transformer TF are arranged counterclockwise.
- the pins #1 to #7 and the pins #8 to #14 are arranged in lines so as to face each other.
- the transformer TF includes the primary winding P, a primary winding P 3 , and the secondary winding S 1 .
- the primary winding P is divided into the winding P 1 and the winding P 2 .
- the winding P 1 serves as an exemplary first winding
- the winding P 2 serves as an exemplary second winding.
- Winding end portions (hereinafter denoted as end portions) P 11 and P 12 of the winding P 1 are connected to the pins #1 and #2, respectively.
- End portions P 21 and P 22 of the winding P 2 are connected to the pins #3 and #4, respectively.
- the end portion P 11 is an exemplary first end portion; the end portion P 12 is an exemplary second end portion; the end portion P 21 is an exemplary third end portion; and the end portion P 22 is an exemplary fourth end portion.
- the winding S 1 has one end portion that branches so as to be connected to the pins #8 to #10, and has the other end portion that branches so as to be connected to the pins #12 to #14.
- the end portions branch in order that, for example, concentration of current is avoided.
- the end portions do not necessarily branch.
- a winding that connects the pin #8 to the pin #14, a winding that connects the pin #9 to the pin #13, and a winding that connects the pin #10 to pin #12 may be bundled together and used.
- the winding P 3 has one end portion connected to the pin #6, and has the other end portion connected to the pin #7.
- the transformer TF may have electrodes instead of pins.
- the surface mounting method is used to connect electrodes to pattern conductors M.
- a pin or electrode may be denoted as a terminal.
- the pins #1 to #7 are exemplary primary terminals. Any configuration may be employed as long as the pins #1 to #7 are arranged in line.
- the expression “in line” may encompass not only the state in which the pins are arranged in a straight line as illustrated in FIGS. 3A and 3B , but also a state in which the pins are shifted in the direction orthogonal to the straight line. Any configuration may be employed as long as the pins are arranged in line in the order of the pin numbers.
- the primary circuit Pc 1 receives a low-voltage alternating current, and supplies a high-frequency alternating current to the primary winding P of the transformer TF.
- the secondary circuit Sc rectifies an alternating current induced in the secondary winding S 1 of the transformer TF, and generates a direct current of 24 V.
- the primary circuit Pc 2 rectifies an alternating current induced in the primary winding P 3 of the transformer TF, and generates a power supply voltage for the control circuit Cc for the field-effect transistor FET which is described below.
- the primary circuits Pc 1 and Pc 2 , the secondary circuit Sc, and the transformer TF are formed on the power supply substrate 71 .
- the primary circuit Pc 1 will be described.
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 3 , M 4 , and M 5 of the power supply substrate 71 .
- the primary circuit Pc 1 includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 3 , and M 4 .
- the primary circuit Pc 1 also includes the capacitor C 1 disposed between the pattern conductors M 3 and M 4 .
- the primary circuit Pc 1 also includes the field-effect transistor FET that serves as a switching device and that is disposed between the pattern conductors M 4 and M 5 .
- the pattern conductors M 1 and M 2 receive an alternating current of 100 V from a commercial power supply.
- the pattern conductors M 1 and M 2 are terminals that receive alternating current.
- the diode bridge DB rectifies the received alternating current, and a pulsating current is output to the pattern conductors M 3 and M 4 .
- the pulsating current that is output to the pattern conductors M 3 and M 4 is a pulsating current obtained through full-wave rectification.
- the capacitor C 1 smooths the pulsating current obtained from the diode bridge DB.
- the field-effect transistor FET switches the direct current obtained through smoothing performed by the capacitor C 1 .
- a high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 3 and M 5 .
- any configuration of the primary winding P may be employed as long as the winding P 1 and the winding P 2 are connected to each other in parallel and the primary winding P is connected to the pattern conductor M 3 and the pattern conductor M 5 .
- the pattern conductor M 3 extends so that the pin #1 (end portion P 11 ) of the transformer TF is connected to the pin #3 (end portion P 21 ) of the transformer TF.
- the pattern conductor M 5 connects the pin #2 (end portion P 12 ) of the transformer TF to the pin #4 (end portion P 22 ) of the transformer TF. That is, in the primary winding P, the pattern conductor M 3 connects the end portion P 11 of the winding P 1 to the end portion P 21 of the winding P 2 , and the pattern conductor M 5 connects the end portion P 12 of the winding P 1 to the end portion P 22 of the winding P 2 . In this manner, the winding P 1 is connected to the winding P 2 in parallel (see FIG. 3A ).
- the distance d 1 between the pattern conductor M 3 of the primary circuit Pc 1 and a pattern conductor M 31 of the secondary circuit Sc is shorter than the distance d 2 between pattern conductors M 6 , M 7 , and M 8 of the primary circuit Pc 1 and pattern conductors M 31 and M 32 of the secondary circuit Sc in the power supply unit 70 of the high-voltage system (200 V) illustrated in FIG. 3B .
- One end (the end portion P 11 and the end portion P 21 ) of the parallel connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 3 , and the other end (the end portion P 12 and the end portion P 22 ) is connected to the pattern conductor M 5 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in parallel in the primary winding P, which induces a high-frequency alternating current to the primary winding P 3 and the secondary winding S 1 .
- the secondary circuit Sc will be described.
- the secondary circuit Sc is formed by using pattern conductors M 31 , M 32 , and M 33 of the power supply substrate 71 .
- the secondary circuit Sc includes the diode D 2 disposed between the pattern conductors M 32 and M 33 .
- the secondary circuit Sc also includes the capacitor C 2 disposed between the pattern conductors M 31 and M 33 .
- the secondary winding S 1 induces a high-frequency alternating current in the pattern conductors M 31 and M 32 . Then, the high-frequency alternating current is rectified by the diode D 2 , and is converted into a pulsating current.
- the pulsating current obtained through rectification performed by the diode D 2 is a pulsating current obtained through half-wave rectification.
- the pulsating current obtained through rectification performed by the diode D 2 is smoothed by the capacitor C 2 .
- the smoothed direct current is output from the pattern conductors M 31 and M 33 .
- the pattern conductors M 31 and M 33 are terminals that output a direct current of 24 V.
- the primary circuit Pc 2 will be described.
- the primary circuit Pc 2 is formed by using pattern conductors M 41 , M 42 , and M 43 of the power supply substrate 71 .
- the primary circuit Pc 2 includes the diode D 3 disposed between the pattern conductors M 42 and M 43 .
- the primary circuit Pc 2 also includes the capacitor C 3 disposed between the pattern conductors M 41 and M 43 .
- the primary winding P 3 induces a high-frequency alternating current in the pattern conductors M 41 and M 42 . Then, the high-frequency alternating current is rectified by the diode D 3 , and is converted into a pulsating current.
- the pulsating current obtained through rectification performed by the diode D 3 is a pulsating current obtained through half-wave rectification.
- the capacitor C 3 smooths the pulsating current obtained through rectification performed by the diode D 3 .
- the smoothed direct current is output from the pattern conductors M 41 and M 43 .
- the pattern conductors M 41 and M 43 are terminals that output a voltage supplied to a control circuit Cc for the field-effect transistor FET, and outputs, for example, a direct current of 20 V.
- the control circuit Cc generates a signal for switching the field-effect transistor FET, and controls the field-effect transistor FET.
- the winding P 1 and the winding P 2 in the primary winding P are connected to each other in parallel.
- the primary circuits Pc 1 and Pc 2 and the secondary circuit Sc in the high-voltage system (200 V) will be described.
- the primary circuit Pc 2 and the secondary circuit Sc are the same as those in the power supply unit 70 of the low-voltage system (100 V), and will not be described.
- the primary circuit Pc 1 is formed by using the pattern conductors M 1 , M 2 , M 4 , M 6 , M 7 , and M 8 of the power supply substrate 71 .
- the pattern conductors M 1 , M 2 , and M 4 are the same as those in the low-voltage system in FIG. 3A .
- the primary circuit Pc 1 includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 6 .
- the primary circuit Pc 1 also includes the capacitor C 1 disposed between the pattern conductors M 4 and M 6 .
- the primary circuit Pc 1 also includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 7 .
- the pattern conductors M 1 and M 2 receive an alternating current of 200 V from a commercial power supply.
- the pattern conductors M 1 and M 2 are terminals that receive alternating current.
- the diode bridge DB rectifies the received alternating current, and a pulsating current is output to the pattern conductors M 4 and M 6 .
- the capacitor C 1 smooths the pulsating current obtained from the diode bridge DB.
- the field-effect transistor FET switches the direct current obtained through smoothing performed by the capacitor C 1 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 6 and M 7 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in series and the primary winding P is connected to the pattern conductor M 6 and the pattern conductor M 7 .
- the pattern conductor M 6 extends so as to be connected to the pin #1 (end portion P 11 ) of the transformer TF.
- the pattern conductor M 7 is connected to the pin #4 (end portion P 22 ) of the transformer TF.
- the pattern conductor M 8 connects the pin #2 (end portion P 12 ) of the transformer TF to the pin #3 (end portion P 21 ) of the transformer TF. That is, in the primary winding P, the pattern conductor M 8 connects the end portion P 12 of the winding P 1 to the end portion P 21 of the winding P 2 . In this manner, the winding P 1 is connected to the winding P 2 in series (see FIG. 2B ).
- One end (the end portion P 11 of the winding P 1 ) of the series connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 6 , and the other end (the end portion P 22 of the winding P 2 ) is connected to the pattern conductor M 7 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current in the secondary winding S 1 .
- connection between the winding P 1 and the winding P 2 is set by using the pattern conductors M disposed on the power supply substrate 71 . That is, the power supply substrate 71 having the pattern conductors M that are different in the low-voltage power supply unit 70 and in the high-voltage power supply unit 70 is prepared, achieving common use of many components included in the transformer TF.
- the power supply substrate 71 having the pattern conductors M that are different in the low-voltage system and the high-voltage system is used.
- the power supply substrate 71 having the pattern conductors M that are the same in the low-voltage system and the high-voltage system is used. That is, in the second exemplary embodiment, the power supply substrate 71 and many components included in the transformer TF are commonly used in the low-voltage system and the high-voltage system.
- FIGS. 4A and 4B illustrate exemplary configurations of the power supply unit 70 to which the second exemplary embodiment is applied.
- FIG. 4A illustrates a low-voltage power supply unit 70
- FIG. 4B illustrates a high-voltage power supply unit 70 .
- a description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and the high-voltage system is a system for alternating current of 200 V.
- Components that are substantially identical to components of the power supply unit 70 to which the first exemplary embodiment is applied are designated with identical reference characters, and will not be described.
- the transformer TF is substantially the same as the transformer TF in the first exemplary embodiment.
- the primary circuit Pc 2 and the secondary circuit Sc are substantially the same as the primary circuit Pc 2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc 1 which is different from the primary circuit Pc 1 in the first exemplary embodiment will be described.
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 4 , M 9 , M 10 , M 11 , and M 12 of the power supply substrate 71 .
- the primary circuit Pc 1 includes connection members J 1 and J 2 .
- the primary circuit Pc 1 also includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 9 .
- the primary circuit Pc 1 also includes the capacitor C 1 disposed between the pattern conductors M 4 and M 9 .
- the primary circuit Pc 1 also includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 10 .
- connection members J 1 and J 2 are, for example, shorting bars that are members formed of a metallic material which is electrically conductive and that are inserted into two holes provided in advance in the power supply substrate 71 so as to electrically connect the holes to each other.
- the connection members J 1 and J 2 may be jumper wires.
- the connection members J 1 and J 2 may be members that are formed as a filter having inductance (L) and resistance (R) and that suppress propagation (passing) of high-frequency noise generated in accordance with the on/off state of the field-effect transistor FET. The same is true for other connection members J described below.
- Operations performed by the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 9 and M 10 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in parallel and the primary winding P is connected to the pattern conductor M 9 and the pattern conductor M 10 .
- the pattern conductor M 9 extends so as to be connected to the pin #1 (end portion P 11 ) of the transformer TF.
- the pattern conductor M 10 extends so as to be connected to the pin #4 (end portion P 22 ) of the transformer TF.
- the pattern conductor M 11 is connected to the pin #2 (end portion P 12 ) of the transformer TF.
- the pattern conductor M 12 is connected to the pin #3 (end portion P 21 ) of the transformer TF.
- connection member J 1 connects the pattern conductor M 9 (end portion P 11 ) to the pattern conductor M 12 (end portion P 21 ).
- connection member J 2 connects the pattern conductor M 10 (end portion P 22 ) to the pattern conductor M 11 (end portion P 12 ).
- connection member J 1 connects the end portion P 11 of the winding P 1 to the end portion P 21 of the winding P 2
- the connection member J 2 connects the end portion P 12 of the winding P 1 to the end portion P 22 of the winding P 2 .
- the winding P 1 is connected to the winding P 2 in parallel (see FIG. 2A ).
- One end (the end portion P 11 and the end portion P 21 ) of the parallel connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 9 , and the other end (the end portion P 12 and the end portion P 22 ) is connected to the pattern conductor M 10 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 in the primary winding P that are connected to each other in parallel, which induces a high-frequency alternating current to the secondary winding S 1 .
- connection member J 1 underlies the transformer TF. In this case, before the transformer TF is mounted, the connection member J 1 may be mounted on the power supply substrate 71 .
- the primary circuit Pc 1 includes a connection member J 3 instead of the connection members J 1 and J 2 in the power supply unit 70 of the low-voltage system (100 V) illustrated in FIG. 4A .
- the other components are substantially the same as components of the power supply unit 70 of the low-voltage system (100 V), and will not be described.
- the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 9 and M 10 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in series and the primary winding P is connected to the pattern conductor M 9 and the pattern conductor M 10 .
- connection member J 3 connects the pattern conductor M 11 (end portion P 12 ) to the pattern conductor M 12 (end portion P 21 ).
- the end portion P 12 of the winding P 1 is connected to the end portion P 21 of the winding P 2 in the primary winding P, and the winding P 1 is connected to the winding P 2 in series (see FIG. 2B ).
- One end (end portion P 11 ) of the series connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 9 , and the other end (end portion P 22 ) is connected to the pattern conductor M 10 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S 1 .
- the power supply substrate 71 and many components included in the transformer TF are commonly used in the low-voltage power supply unit 70 and the high-voltage power supply unit 70 .
- the connection members J 1 , J 2 , and J 3 are used to set a connection relationship (parallel connection or series connection) between the winding P 1 and the winding P 2 in the primary winding P.
- the power supply substrate 71 is easily managed.
- the distance d 1 between the pattern conductor M 3 of the primary circuit Pc 1 and the pattern conductor M 31 of the secondary circuit Sc in the power supply unit 70 of the low-voltage system (100 V) illustrated in FIG. 3A is shorter than the distance d 2 between the pattern conductors M 6 , M 7 , and M 8 of the primary circuit Pc 1 and the pattern conductors M 31 and M 32 of the secondary circuit Sc in the power supply unit 70 of the high-voltage system (200 V) illustrated in FIG. 3B .
- the distance between the pin #1 and the pin #14 is the same in the first exemplary embodiment and the second exemplary embodiment, the distance d 3 between the pattern conductors M 9 and M 12 of the primary circuit Pc 1 and the pattern conductor M 31 of the secondary circuit Sc is shorter than the distance d 2 in the power supply unit 70 of the high-voltage system (200 V) according to the first exemplary embodiment illustrated in FIG. 3B . Therefore, the electric field in this portion is high.
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 . Since the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is determined according to a safety standard, it is necessary to keep a necessary and sufficient distance. Accordingly, if the distance d 1 and the distance d 3 are equal to the distance d 2 , the size of the apparatus is increased.
- FIGS. 5A and 5B illustrate exemplary configurations of the power supply unit 70 to which a third exemplary embodiment is applied.
- FIG. 5A illustrates a low-voltage power supply unit 70
- FIG. 5B illustrates a high-voltage power supply unit 70 .
- a description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V, and the high-voltage system is a system for alternating current of 200 V.
- Components substantially identical to components in power supply unit 70 to which the first exemplary embodiment and the second exemplary embodiment are applied are designated with identical reference characters, and will not be described.
- the transformer TF is substantially the same as the transformer TF in the first exemplary embodiment.
- the primary circuit Pc 2 and the secondary circuit Sc are substantially the same as the primary circuit Pc 2 and the secondary circuit Sc in the first exemplary embodiment.
- the primary circuit Pc 1 that is different from the primary circuit Pc 1 in the first exemplary embodiment will be described.
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 4 , M 13 , M 14 , and M 15 of the power supply substrate 71 .
- the primary circuit Pc 1 includes a connection member J 4 .
- the primary circuit Pc 1 also includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 13 .
- the primary circuit Pc 1 also includes the capacitor C 1 disposed between the pattern conductors M 4 and M 13 .
- the primary circuit Pc 1 also includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 14 .
- Operations performed by the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 13 and M 14 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in parallel and the primary winding P is connected to the pattern conductors M 13 and M 14 .
- the pattern conductor M 13 extends so as to be connected to the pin #1 (end portion P 11 ) of the transformer TF.
- the pattern conductor M 14 is disposed so as to connect the pin #2 (end portion P 12 ) of the transformer TF to the pin #4 (end portion P 22 ) of the transformer TF.
- the pattern conductor M 15 is connected to the pin #3 (end portion P 21 ) of the transformer TF.
- connection member J 4 connects the pattern conductor M 13 (end portion P 11 ) to the pattern conductor M 15 (end portion P 21 ).
- connection member J 4 connects the end portion P 11 of the winding P 1 to the end portion P 21 of the winding P 2
- the pattern conductor M 14 connects the end portion P 12 of the winding P 1 to the end portion P 22 of the winding P 2
- the pattern conductor M 14 is disposed so as to detour around the pattern conductor M 15 on the primary circuit Pc side, and connects the end portion P 12 to the end portion P 22 .
- the winding P 1 is connected to the winding P 2 in parallel (see FIG. 2A ).
- the pattern conductor M 14 may be called a connection pattern conductor.
- One end (the end portion P 11 and the end portion P 21 ) of the parallel connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 13 , and the other end (the end portion P 12 and the end portion P 22 ) is connected to the pattern conductor M 14 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected in parallel in the primary winding P, which induces a high-frequency alternating current to the secondary winding S 1 .
- connection member J 4 connects the pin #1 (end portion P 11 ) of the transformer TF to the pin #3 (end portion P 21 ) of the transformer TF, and the pattern conductor M 14 connects the pin #2 (end portion P 12 ) to the pin #4 (end portion P 22 ).
- the distance between the pattern conductors M 13 , M 14 , and M 15 of the primary circuit Pc 1 and the pattern conductor M 31 of the secondary circuit Sc is set to the distance d 2 .
- the primary circuit Pc 1 in the power supply unit 70 of the high-voltage system (200 V) illustrated in FIG. 5B is the same as that in the power supply unit 70 of the high-voltage system (200 V) in the first exemplary embodiment illustrated in FIG. 3B .
- the distance between the pattern conductors M 6 , M 7 , and M 8 of the primary circuit Pc 1 and the pattern conductors M 31 and M 32 of the secondary circuit Sc in the power supply unit 70 of the high-voltage system (200 V) illustrated in FIG. 3B is set to the distance d 2 .
- the power supply unit 70 to which a fourth exemplary embodiment is applied is smaller than the power supply units 70 in the first to third exemplary embodiments. That is, the size of the power supply substrate 71 is smaller.
- the end portion P 21 is interposed between the end portion P 12 and the end portion P 22 . Therefore, the pattern conductor M 5 is provided. Accordingly, when the power supply substrate 71 having the same size is used, a region a (a region surrounded by the pattern conductors M 4 , M 6 , M 7 , and M 8 ) is not used in the high-voltage power supply unit 70 illustrated in FIG. 3B , resulting in an increase in the size of the power supply substrate 71 .
- the end portion P 21 is interposed between the end portion P 12 and the end portion P 22 . Therefore, the pattern conductor M 14 is provided. Accordingly, the region a (the region surrounded by the pattern conductors M 4 , M 6 , M 7 , and M 8 ) illustrated in FIG. 5B is not used, resulting in an increase in the size of the power supply substrate 71 .
- FIGS. 6A and 6B illustrate exemplary configurations of the power supply unit 70 to which the fourth exemplary embodiment is applied.
- FIG. 6A illustrates a low-voltage power supply unit 70
- FIG. 6B illustrates a high-voltage power supply unit 70 .
- a description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and that the high-voltage system is a system for alternating current of 200 V.
- Components substantially identical to components in the first exemplary embodiment are designated with identical reference characters, and will not be described.
- the transformer TF will be described. As described above, the transformer TF is commonly used in the low-voltage power supply unit 70 ( FIG. 6A ) and the high-voltage power supply unit 70 ( FIG. 6B ).
- pins #1 to #14 of the transformer TF are the same as the number and arrangement in the first exemplary embodiment.
- the transformer TF includes the primary winding P (windings P 1 and P 2 ) and the secondary winding S 1 .
- the connection relationship indicating how pins are connected to the windings P 1 and P 2 in the fourth exemplary embodiment is different from the connection relationship in the first and third exemplary embodiments.
- the end portion P 11 is connected to the pin #1, and the end portion P 12 is connected to the pin #3.
- the end portion P 21 is connected to the pin #2, and the end portion P 22 is connected to the pin #4.
- the winding S 1 and the winding P 3 are substantially the same as the winding S 1 and the winding P 3 in the first exemplary embodiment, and will not be described.
- the primary circuit Pc 2 and the secondary circuit Sc are substantially the same as the primary circuit Pc 2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc 1 will be described.
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 4 , M 20 , and M 21 of the power supply substrate 71 .
- the primary circuit Pc 1 includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 20 .
- the primary circuit Pc 1 includes the capacitor C 1 disposed between the pattern conductors M 4 and M 20 .
- the primary circuit Pc 1 includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 21 .
- Operation of the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 20 and M 21 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in parallel and the primary winding P is connected to the pattern conductors M 20 and M 21 .
- the pattern conductor M 20 extends so as to be connected to the pin #1 (end portion P 11 ) and the pin #2 (end portion P 21 ) of the transformer TF.
- the pattern conductor M 21 is disposed so as to connect the pin #3 (end portion P 12 ) of the transformer TF to the pin #4 (end portion P 22 ) of the transformer TF.
- the pattern conductor M 20 connects the end portion P 11 of the winding P 1 to the end portion P 21 of the winding P 2 in the primary winding P
- the pattern conductor M 21 connects the end portion P 12 of the winding P 1 and the end portion P 22 of the winding P 2 .
- the winding P 1 is connected to the winding P 2 in parallel (see FIG. 2A ).
- One end (the end portion P 11 and the end portion P 21 ) of the parallel connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 20 , and the other end (the end portion P 12 and the end portion P 22 ) is connected to the pattern conductor M 21 .
- connection relationship of pins in the winding P 1 is different from the connection relationship in the winding P 2 .
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 .
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc in the power supply unit 70 of the low-voltage system (100 V) illustrated in FIG. 5A is set to the distance d 2 .
- connection is made by using the connection member J 4 at one end (the end portion P 11 and the end portion P 21 ), and connection is made by using the pattern conductor M 14 at the other end (the end portion P 12 and the end portion P 22 ). That is, electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced).
- connection is made by using the pattern conductor M 20 at one end (the end portion P 11 and the end portion P 21 ), and connection is made by using the pattern conductor M 21 at the other end (the end portion P 12 and the end portion P 22 ).
- electric characteristics at one end of the primary winding P and electric characteristics at the other end are not asymmetrical (balanced).
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 4 , M 22 , M 23 , and M 24 of the power supply substrate 71 .
- the primary circuit Pc 1 includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 22 .
- the primary circuit Pc 1 includes the capacitor C 1 disposed between the pattern conductors M 4 and M 22 .
- the primary circuit Pc 1 includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 24 .
- Operations performed by the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 22 and M 24 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in series and the primary winding P is connected to the pattern conductors M 22 and M 24 .
- the pattern conductor M 22 extends so as to be connected to the pin #1 (end portion P 11 ) of the transformer TF.
- the pattern conductor M 23 is disposed so as to connect the pin #2 (end portion P 21 ) of the transformer TF to the pin #3 (end portion P 12 ) of the transformer TF.
- the pattern conductor M 24 is disposed so as to be connected to the pin #4 (end portion P 22 ) of the transformer TF.
- the pattern conductor M 23 connects the end portion P 12 of the winding P 1 to the end portion P 21 of the winding P 2 in the primary winding P.
- the winding P 1 is connected to the winding P 2 in series (see FIG. 2B ).
- One end (end portion P 11 ) of the series connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 22 , and the other end (end portion P 22 ) is connected to the pattern conductor M 24 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S 1 .
- connection relationship of pins in the winding P 1 is different from the connection relationship in the winding P 2 so that the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 .
- a region surrounded by the pattern conductors M 4 , M 22 , M 23 , and M 24 is smaller than the regions a illustrated in FIGS. 3B and 5B .
- connection relationship indicating how pins are connected to the windings P 1 and P 2 of the primary winding P in the transformer TF is different from the connection relationship in the first exemplary embodiment.
- many components included in the transformer TF are commonly used, and the size of the power supply substrate 71 is smaller than the size in the first exemplary embodiment.
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 .
- the low-voltage power supply unit 70 the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical is avoided.
- the shapes of pattern conductors M of the power supply substrate 71 of the low-voltage power supply unit 70 are different from the shapes for the high-voltage power supply unit 70 .
- a connection member J does not need to be used.
- the end portions connecting the winding P 1 of the transformer TF to the winding P 2 are disposed adjacent to each other.
- the power supply unit 70 to which the fourth exemplary embodiment is applied uses the power supply substrate 71 on which different pattern conductors M are used in the low-voltage power supply unit 70 and the high-voltage power supply unit 70 .
- the power supply unit 70 to which a fifth exemplary embodiment is applied uses the power supply substrates 71 on which the same pattern conductors M are used in the low-voltage power supply unit 70 and the high-voltage power supply unit 70 .
- FIGS. 7A and 7B illustrate exemplary configurations of the power supply unit 70 to which the fifth exemplary embodiment is applied.
- FIG. 7A illustrates a low-voltage power supply unit 70
- FIG. 7B illustrates a high-voltage power supply unit 70 .
- a description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and that the high-voltage system is a system for alternating current of 200 V.
- Components substantially identical to components in the first exemplary embodiment are designated with identical reference characters, and will not be described.
- the transformer TF is substantially the same as the transformer TF in the fourth exemplary embodiment, and will not be described.
- the primary circuit Pc 2 and the secondary circuit Sc are substantially the same as the primary circuit Pc 2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc 1 that is different from the primary circuit Pc 1 in the first exemplary embodiment will be described.
- the primary circuit Pc 1 is formed by using pattern conductors M 1 , M 2 , M 4 , M 25 , M 26 , M 27 , and M 28 of the power supply substrate 71 .
- the primary circuit Pc 1 includes connection members J 5 and J 6 .
- the primary circuit Pc 1 also includes the diode bridge DB disposed among the pattern conductors M 1 , M 2 , M 4 , and M 25 .
- the primary circuit Pc 1 also includes the capacitor C 1 disposed between the pattern conductors M 4 and M 25 .
- the primary circuit Pc 1 also includes the field-effect transistor FET disposed between the pattern conductors M 4 and M 28 .
- Operations performed by the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 25 and M 28 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in parallel and the primary winding P is connected to the pattern conductors M 25 and M 28 .
- the pattern conductor M 25 extends so as to be connected to the pin #1 (end portion P 11 ) of the transformer TF.
- the pattern conductor M 26 is connected to the pin #2 (end portion P 21 ) of the transformer TF.
- the pattern conductor M 27 is connected to the pin #3 (end portion P 12 ) of the transformer TF.
- the pattern conductor M 28 is connected to the pin #4 (end portion P 22 ) of the transformer TF.
- connection member J 5 connects the pattern conductor M 25 to the pattern conductor M 26
- connection member J 6 connects the pattern conductor M 27 to the pattern conductor M 28 .
- connection member J 5 connects the end portion P 11 of the winding P 1 to the end portion P 21 of the winding P 2 in the primary winding P
- connection member J 6 connects the end portion P 12 of the winding P 1 to the end portion P 22 of the winding P 2 .
- the winding P 1 is connected to the winding P 2 in parallel (see FIG. 2A ).
- One end (the end portion P 11 and the end portion P 21 ) of the parallel connection between the winding P 1 and the winding P 2 is connected to the pattern conductor M 25 , and the other end (the end portion P 12 and the end portion P 22 ) is connected to the pattern conductor M 28 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in parallel in the primary winding P, which induces a high-frequency alternating current to the secondary winding S 1 .
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 .
- connection is made by using the connection member J 5 at one end (the end portion P 11 and the end portion P 21 ) of the primary winding P, and connection is made by using the connection member J 6 at the other end (the end portion P 12 and the end portion P 22 ). Accordingly, the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced) is avoided.
- connection member J 5 A setting is made so that the difference in impedance between the connection member J 5 and the connection member J 6 is reduced.
- the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced) is further avoided.
- the pattern conductors M 1 , M 2 , M 4 , M 25 , M 26 , M 27 , and M 28 of the power supply substrate 71 of the primary circuit Pc 1 are substantially the same as the pattern conductors M 1 , M 2 , M 4 , M 25 , M 26 , M 27 , and M 28 of the power supply unit 70 of the low-voltage system (100 V) in FIG. 7A .
- the connection relationships of the diode bridge DB, the capacitor C 1 , and the field-effect transistor FET are the same as the connection relationships in FIG. 7A .
- the primary circuit Pc 1 includes a connection member J 7 instead of the connection members J 5 and J 6 of the power supply unit 70 of the low-voltage system (100 V) in FIG. 7A .
- Operations performed by the primary circuit Pc 1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M 25 and M 28 .
- any configuration of the primary winding P may be employed as long as the winding P 1 is connected to the winding P 2 in series and the primary winding P is connected to the pattern conductors M 25 and M 28 .
- connection member J 7 connects the pattern conductor M 26 to the pattern conductor M 27 .
- connection member J 7 connects the end portion P 12 of the winding P 1 to the end portion P 21 of the winding P 2 in the primary winding P.
- the winding P 1 is connected to the winding P 2 in series (see FIG. 2B ).
- One end (end portion P 11 ) of the winding P in which series connection is made is connected to the pattern conductor M 25 , and the other end (end portion P 22 ) is connected to the pattern conductor M 28 .
- the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P 1 and the winding P 2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S 1 .
- the pin #1 (end portion P 11 ) and the pin #4 (end portion P 22 ) between which the potential difference is the largest are disposed apart with the pin #2 (end portion P 21 ) and the pin #3 (end portion P 12 ) that are at a midpoint potential and that are interposed between the pin #1 and the pin #4. Accordingly, a high electric field is unlikely to be produced between the pins and between the pattern conductors M connected to the pins.
- the low-voltage power supply unit 70 and the high-voltage power supply unit 70 are commonly used in the low-voltage power supply unit 70 and the high-voltage power supply unit 70 .
- the power supply substrate 71 is also commonly used. Setting of the low-voltage power supply unit 70 and the high-voltage power supply unit 70 is made by using the connection members J.
- the distance between the pattern conductors M of the primary circuit Pc 1 and the pattern conductors M of the secondary circuit Sc is set to the distance d 2 in the low-voltage power supply unit 70 and the high-voltage power supply unit 70 .
- the end portions connecting the winding P 1 and the winding P 2 of the transformer TF are disposed adjacent to each other.
- the connecting end portions of the transformer TF are disposed adjacent to each other.
- the state in which the winding P 1 and the winding P 2 are disposed in parallel in the primary winding P is described.
- the winding P 1 and the winding P 2 may be provided in any winding manner such as overlap winding. Any configuration may be employed as long as the terminals of the winding P 1 and the winding P 2 in the primary winding P are arranged as described in the first to fifth exemplary embodiments.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Dc-Dc Converters (AREA)
- Electrophotography Configuration And Component (AREA)
Abstract
Description
- This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2016-250150 filed Dec. 22, 2016.
- The present invention relates to a power supply unit.
- A power supply unit supplying a predetermined voltage is formed by using a transformer corresponding to the voltage supplied from a commercial power supply.
- According to an aspect of the invention, there is provided a power supply unit including a primary circuit, a transformer, and a secondary circuit. The primary circuit is connected to an alternating-current power supply and includes a switching device. The transformer includes a primary winding and a secondary winding. The primary winding receives an alternating current in such a manner that an alternating current is induced in the secondary winding. The received alternating current is generated through switching using the switching device. The secondary circuit rectifies, for output, the alternating current induced in the secondary winding. The primary winding includes a first winding and a second winding. When the alternating-current power supply is a power supply of a first voltage, the first winding is connected to the second winding in parallel in the primary winding. When the alternating-current power supply is a power supply of a second voltage higher than the first voltage, the first winding is connected to the second winding in series in the primary winding.
- Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein:
-
FIG. 1 is a schematic sectional view of an image forming apparatus; -
FIG. 2A is a diagram for describing an overview of a transformer in a power supply unit to which a first exemplary embodiment is applied and which receives low-voltage alternating current; -
FIG. 2B is a diagram for describing an overview of a transformer in a power supply unit to which the first exemplary embodiment is applied and which receives high-voltage alternating current; -
FIG. 3A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which the first exemplary embodiment is applied; -
FIG. 3B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the first exemplary embodiment is applied; -
FIG. 4A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a second exemplary embodiment is applied; -
FIG. 4B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the second exemplary embodiment is applied; -
FIG. 5A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a third exemplary embodiment is applied; -
FIG. 5B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the third exemplary embodiment is applied; -
FIG. 6A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a fourth exemplary embodiment is applied; -
FIG. 6B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the fourth exemplary embodiment is applied; -
FIG. 7A is a diagram illustrating an exemplary configuration of a low-voltage power supply unit to which a fifth exemplary embodiment is applied; and -
FIG. 7B is a diagram illustrating an exemplary configuration of a high-voltage power supply unit to which the fifth exemplary embodiment is applied. - Exemplary embodiments of the present invention will be described below with reference to the attached drawings.
-
Image Forming Apparatus 1 -
FIG. 1 is a schematic sectional view of animage forming apparatus 1. The illustratedimage forming apparatus 1 is an electrophotographic color printer that prints an image on the basis of image data. - The
image forming apparatus 1 includes, within abody case 90, asheet accommodating unit 40 in which sheets Q are accommodated, animage forming unit 10 that forms an image on a sheet Q, and aconveying unit 50 that conveys a sheet Q from thesheet accommodating unit 40 through theimage forming unit 10 to asheet eject portion 96 of thebody case 90. Theimage forming apparatus 1 also includes acontroller 31 that controls the entire operations of theimage forming apparatus 1, acommunication unit 32 that communicates, for example, with a personal computer (PC) 3, an image reading apparatus (scanner) 4, and the like and that receives image data, and animage processor 33 that performs image processing on image data received by thecommunication unit 32. Theimage forming apparatus 1 further includes an image-formationpower supply unit 80 for supplying high-voltage power to theimage forming unit 10. Theimage forming apparatus 1 furthermore includes apower supply unit 70 that receives an alternating current from a commercial power supply and that supplies direct-current power to the image-formationpower supply unit 80, thecontroller 31, thecommunication unit 32, and theimage processor 33. Thepower supply unit 70 serves as an exemplary power supply unit. - The
sheet accommodating unit 40 contains the sheets Q. Theconveying unit 50 includes atransport path 51 for a sheet Q andconveying rollers 52. Thetransport path 51 extends from thesheet accommodating unit 40 through theimage forming unit 10 to thesheet eject portion 96. Theconveying rollers 52 convey a sheet Q along thetransport path 51. Theconveying unit 50 conveys a sheet Q in the arrow C direction. - The
image forming unit 10 includes fourimage forming units image forming units image forming units image forming units 11. Eachimage forming unit 11 includes aphotoconductor drum 12, acharger 13, a light emitting diode (LED)print head 14, a developingunit 15, and adrum cleaner 16. Thephotoconductor drum 12 forms an electrostatic latent image and holds a toner image. Thecharger 13 charges the surface of thephotoconductor drum 12 with a predetermined potential. TheLED print head 14 exposes thephotoconductor drum 12 charged by thecharger 13, to light on the basis of image data of the corresponding color. The developingunit 15 develops an electrostatic latent image formed on the surface of thephotoconductor drum 12. Thedrum cleaner 16 cleans the surface of thephotoconductor drum 12 after transfer. - The four
image forming units unit 15, and theimage forming unit 11Y including the developingunit 15 containing yellow (Y) toner forms a yellow toner image. Similarly, theimage forming unit 11M including the developingunit 15 containing magenta (M) toner forms a magenta toner image; the image forming unit 11C including the developingunit 15 containing cyan (C) toner forms a cyan toner image; and theimage forming unit 11K including the developingunit 15 containing black (K) toner forms a black toner image. - The
image forming unit 10 includes anintermediate transfer belt 20 andfirst transfer rollers 21. On theintermediate transfer belt 20, the color toner images formed on the photoconductor drums 12 of theimage forming units 11 are transferred on top of one another so as to be superimposed on one another. Thefirst transfer rollers 21 sequentially performs electrostatic transfer (first transfer) onto theintermediate transfer belt 20, on the color toner images formed by theimage forming units 11. Further, theimage forming unit 10 includes a second transfer roller 22 and a fixingunit 60. The second transfer roller 22 performs electrostatic transfer (second transfer) onto a sheet Q at a time, on the superimposed toner images obtained by transferring the color toner images onto the surface of theintermediate transfer belt 20 in a superimposed manner. The fixingunit 60 fixes the superimposed toner images that have been subjected to second transfer onto the sheet Q. - The
image forming apparatus 1 performs an image forming process through the following processes under operation control exerted by thecontroller 31. That is, image data transmitted from thePC 3 or thescanner 4 is received by thecommunication unit 32. After theimage processor 33 performs predetermined image processing on the image data, the image data is converted into image data of each color which is transmitted to theimage forming unit 11 for the corresponding color. For example, in theimage forming unit 11K that forms a black toner image, while rotating in the arrow A direction, thephotoconductor drum 12 is charged at a predetermined potential by thecharger 13. - After that, the
print head 14 scans and exposes, to light, thephotoconductor drum 12 on the basis of black image data transmitted from theimage processor 33. Thus, an electrostatic latent image corresponding to the black image data is formed on the surface of thephotoconductor drum 12. The black electrostatic latent image formed on thephotoconductor drum 12 is developed by the developingunit 15, and a black toner image is formed on thephotoconductor drum 12. Similarly, theimage forming units - The
first transfer rollers 21 are used to sequentially perform electrostatic transfer on the color toner images formed on the photoconductor drums 12 of theimage forming units 11, onto theintermediate transfer belt 20 that moves in the arrow B direction, and the superimposed toner images obtained by superimposing the color toner images are formed on theintermediate transfer belt 20. - The
intermediate transfer belt 20 moves in the arrow B direction so that the superimposed toner images on theintermediate transfer belt 20 are conveyed to the second transfer roller 22. At the timing at which the superimposed toner images are conveyed to the second transfer roller 22, the conveyingrollers 52 of the conveyingunit 50 convey a sheet Q from thesheet accommodating unit 40 in the arrow C direction along thetransport path 51. The superimposed toner images formed on theintermediate transfer belt 20 are subjected to electrostatic transfer at a time onto the sheet Q conveyed along thetransport path 51, due to a transfer electric field formed by the second transfer roller 22. - After that, the sheet Q onto which electrostatic transfer has been performed on the superimposed toner images is conveyed to the fixing
unit 60 along thetransport path 51. The fixingunit 60 applies heating and pressure to fix, onto the sheet Q, the superimposed toner images on the sheet Q which have been conveyed to the fixingunit 60. The sheet Q on which the fixed superimposed toner images are formed is conveyed in the arrow C direction along thetransport path 51, and is ejected from thesheet eject portion 96 of thebody case 90. Then, the sheet Q is loaded on thesheet loading unit 95 on which sheets are to be put. - In contrast, remaining toner on the photoconductor drums 12 after first transfer and remaining toner on the
intermediate transfer belt 20 after second transfer are removed by thedrum cleaners 16 and abelt cleaner 25, respectively. - The process of the
image forming apparatus 1 printing an image on a sheet Q is repeatedly performed in cycles, the number of which corresponds to the number of copies. - The
power supply unit 70 receives an alternating current from a commercial power supply (alternating-current power supply), supplies, for example, a direct current of 24 V to the image-formationpower supply unit 80, and supplies, for example, a direct current of 5 V to thecontroller 31, thecommunication unit 32, and theimage processor 33. - There are a low-voltage system (90V to 140V) and a high-voltage system (196V to 264V) as the voltage of a commercial power supply. Therefore, the
image forming apparatus 1 includes thepower supply unit 70 corresponding to the voltage of a commercial power supply from which power is received (supplied). - The
power supply unit 70 uses a switching regulator system using a switching device. A transformer TF is used for the voltage conversion. -
FIGS. 2A and 2B are diagrams for describing an overview of the transformer TF in thepower supply unit 70 to which the first exemplary embodiment is applied.FIG. 2A illustrates a case in which a low-voltage alternating current is received, andFIG. 2B illustrates a case in which a high-voltage alternating current is received. InFIGS. 2A and 2B , a low-voltage system of, for example, 120 V, and a high-voltage system of, for example, 240 V are illustrated. In addition, in each of the upper portions ofFIGS. 2A and 2B , the relationship of winding numbers in the transformer TF is illustrated, and, in each of the lower portions, the configuration of a primary winding P is illustrated. - In the description below, a case in which a low-voltage alternating current is received is denoted as a case of a low-voltage system, and a case in which a high-voltage alternating current is received is denoted as a case of a high-voltage system.
- As illustrated in the upper portion in
FIG. 2A , in the case of a low-voltage system (in this example, 120 V), the winding number NP of the primary winding P of the transformer TF is 50 turns (T), and the winding number NS1 of a secondary winding S1 is 10 T. Accordingly, 24 V is obtained from 120 V. - In contrast, as illustrated in the upper portion in
FIG. 2B , in the case of a high-voltage system (in this example, 240 V) (hereinafter denoted as the case of a high-voltage system), the winding number NP of the primary winding P of the transformer TF is 100 T, and the winding number NS1 of the secondary winding S1 is 10 T. Thus, 24 V is obtained from 240 V. - That is, in both of the case of a low-voltage system and the case of a high-voltage system, the winding number NS1 of the secondary winding S1 is 10 T. However, the winding number NP of the primary winding P in the case of a low-voltage system, i.e., 50 T, is different from the winding number NP in the case of a high-voltage system, i.e., 100 T. Therefore, if this configuration is used, it is not possible to commonly use the transformer TF in the low-voltage system and the high-voltage system.
- Accordingly, the transformer TF to which the first exemplary embodiment is applied employs a configuration in which the primary winding P is divided into two windings P1 and P2, each of which has a winding number NP of 50 T. In the case of a low-voltage system, the winding P1 and the winding P2 are connected to each other in parallel. Thus, the winding number NP of the primary winding P is 50 T. In contrast, in the case of a high-voltage system, the winding P1 and the winding P2 are connected to each other in series. Thus, the winding number NP of the primary winding P is 100 T.
- Each of the windings P1 and P2 is wound so that voltage is generated in the same direction with respect to the secondary winding S1.
- This configuration enables many components included in the transformer TF to be commonly used for both of a low-voltage alternating current and a high-voltage alternating current that are received by the
image forming apparatus 1. Therefore, it is not necessary to prepare different transformers TF for theimage forming apparatus 1 receiving a low-voltage alternating current and theimage forming apparatus 1 receiving a high-voltage alternating current, achieving simple management of components and reduction in cost. - In the configuration in which the primary winding P is divided into the winding P1 (having inductance L1 and direct current resistance R1) and the winding P2 (having inductance L2 and direct current resistance R2), the inductance is equal to L1+L2 in the case of series connection, and the inductance is equal to 1/(1/
L1+ 1/L2) in the case of parallel connection. The direct current resistance is equal to 1/(1/R1+1/R2) in the case of parallel connection, and the direct current resistance is equal to R1+R2 in the case of series connection. - Assume that L1=L2=L. The inductance is equal to 2 L in the case of series connection, and is equal to L/2 in the case of parallel connection. Assume that R1=R2=R. The direct current resistance is equal to R/2 in the case of parallel connection, and is equal to 2 R in the case of series connection. That is, the direct current resistance obtained in the case of a low-voltage system is a quarter of the direct current resistance of a high-voltage system.
- The loss (heating value) produced due to the direct current resistance of the primary winding P is proportional to the multiplication product of the square of a current and the direct current resistance. Therefore, when the same power is to be supplied to the secondary winding S1 (24 V side), the current in the low-voltage system that is twice the current in the high-voltage system needs to flow. However, since the direct current resistance in the low-voltage system is a quarter of the direct current resistance in the high-voltage system, the loss (heating value) is the same.
- In the case of a low-voltage system, even when one of the winding P1 and the winding P2 of the primary winding P is used, 24 V may be obtained from the low-voltage system (120 V). However, the direct current resistance obtained in the case of a low-voltage system is equal to R and is half the direct current resistance obtained in the case of a high-voltage system.
- Therefore, when the same amount of power is to be applied to the secondary winding S1 (24 V side), the loss (heating value) in the primary winding P in the low-voltage system is twice the loss in the high-voltage system.
- Table 1 describes an exemplary configuration of the transformer to which the first exemplary embodiment is applied. The primary winding P is divided into the two windings P1 and P2. Table 1 describes the winding numbers NP1 and NP2 and the inductances LP1 and LP2 for the windings P1 and P2. Further, Table 1 describes the winding number and the inductance of the primary winding P in the low-voltage system and the winding number and the inductance in the high-voltage system, and also describes an exemplary maximum current IPMAX that flows through the primary winding P.
-
TABLE 1 Configuration of primary winding P Low-voltage High-voltage (windings P1 and P2) system system Winding number NP1 40 T 40 T 80 T NP2 40 T Inductance LP1 512 μH 256 μH 1024 μH LP2 512 μH Maximum current IPMAX 5.50 A 2.75 A flowing through primary winding P - As described in Table 1, the maximum current IPMAX that flows through the primary winding P in the low-voltage system is twice the maximum current IPMAX in the high-voltage system. Accordingly, as the direct current resistance is smaller, the loss (heating value) may be made smaller.
- In the description above, the case in which a low-voltage system of 120 V and a high-voltage system of 240 V are used and in which the voltage of the high-voltage alternating current is twice the voltage of the low-voltage alternating current is described. As described above, widely-used commercial power supplies are low-voltage systems of 90 V to 140 V and high-voltage systems of 196 V to 264 V. That is, the voltage of a high-voltage system is approximately twice the voltage of a low-voltage system. Therefore, the first exemplary embodiment may be applied to these voltages.
- The low-voltage system serves as an exemplary first voltage, and the high-voltage system serves as an exemplary second voltage. In addition, the low-voltage system is an exemplary 100 V system, and the high-voltage system is an exemplary 200 V system.
- The configuration of the
power supply unit 70 to which the first exemplary embodiment is applied will be described. -
FIGS. 3A and 3B illustrate exemplary configurations of thepower supply unit 70 to which the first exemplary embodiment is applied.FIG. 3A illustrates a low-voltagepower supply unit 70, andFIG. 3B illustrates a high-voltagepower supply unit 70. A description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and the high-voltage system is a system for alternating current of 200 V. Accordingly, the low-voltage system is denoted as 100 V or a low-voltage system (100 V), and the high-voltage system is denoted as 200 V or a high-voltage system (200 V). A description will be made under the assumption that thepower supply unit 70 outputs a direct current of 24 V. - The
power supply unit 70 includes apower supply substrate 71, electronic components mounted on thepower supply substrate 71, and the transformer TF mounted on thepower supply substrate 71. Thepower supply substrate 71 includes an insulated substrate formed of paper-based phenol, glass epoxy, or the like, and multiple pattern conductors M that are formed of copper foil or the like on one of the surfaces of the insulated substrate. Typically, thepower supply substrate 71 is formed of a single-layer board having one surface on which a conductor layer such as copper foil is formed. Therefore, thepower supply substrate 71 is formed of a single-layer board, and has, on one of the surfaces, the pattern conductors M formed by processing the conductor layer. Thepower supply substrate 71 may be formed, for example, of a double-sided board having conductor layers formed on both of the surfaces, or a multilayer board including multiple conductor layers. - The size of the
power supply substrate 71 of the low-voltagepower supply unit 70 is the same as the size of thepower supply substrate 71 of the high-voltagepower supply unit 70. - When the multiple pattern conductors M are to be distinguished from one another, each of the pattern conductors M is denoted as a pattern conductor Mx. The symbol ‘x’ indicates a number for identifying the pattern conductor. The same is true for other components.
- The electronic components are a diode bridge DB, a field-effect transistor FET, capacitors C1, C2, and C3, and diodes D2 and D3 which are connected to either one of the pattern conductors M.
- The transformer TF will be described. As described above, the transformer TF is commonly used in the low-voltage system (
FIG. 3A ) and the high-voltage system (FIG. 3B ). - The transformer TF is formed as an electronic component having 14 pins (
pins # 1 to #14). The 14 pins are inserted into holes disposed in thepower supply substrate 71, and each are connected to a corresponding one of the pattern conductors M. Thus, the transformer TF is electrically connected to pattern conductors M of thepower supply substrate 71 through the pins, and is fixed to thepower supply substrate 71. - The
pins # 1 to #14 of the transformer TF are arranged counterclockwise. Thepins # 1 to #7 and thepins # 8 to #14 are arranged in lines so as to face each other. - The transformer TF includes the primary winding P, a primary winding P3, and the secondary winding S1. The primary winding P is divided into the winding P1 and the winding P2. The winding P1 serves as an exemplary first winding, and the winding P2 serves as an exemplary second winding.
- Winding end portions (hereinafter denoted as end portions) P11 and P12 of the winding P1 are connected to the
pins # 1 and #2, respectively. End portions P21 and P22 of the winding P2 are connected to thepins # 3 and #4, respectively. The end portion P11 is an exemplary first end portion; the end portion P12 is an exemplary second end portion; the end portion P21 is an exemplary third end portion; and the end portion P22 is an exemplary fourth end portion. - The winding S1 has one end portion that branches so as to be connected to the
pins # 8 to #10, and has the other end portion that branches so as to be connected to thepins # 12 to #14. The end portions branch in order that, for example, concentration of current is avoided. The end portions do not necessarily branch. A winding that connects thepin # 8 to thepin # 14, a winding that connects thepin # 9 to thepin # 13, and a winding that connects thepin # 10 to pin #12 may be bundled together and used. - The winding P3 has one end portion connected to the
pin # 6, and has the other end portion connected to thepin # 7. - Nothing is connected to the
pins # 5 and #11. - The transformer TF may have electrodes instead of pins. The surface mounting method is used to connect electrodes to pattern conductors M.
- A pin or electrode may be denoted as a terminal. The
pins # 1 to #7 are exemplary primary terminals. Any configuration may be employed as long as thepins # 1 to #7 are arranged in line. The expression “in line” may encompass not only the state in which the pins are arranged in a straight line as illustrated inFIGS. 3A and 3B , but also a state in which the pins are shifted in the direction orthogonal to the straight line. Any configuration may be employed as long as the pins are arranged in line in the order of the pin numbers. - By using
FIG. 3A , primary circuits Pc1 and Pc2 and a secondary circuit Sc in thepower supply unit 70 of the low-voltage system (100 V) will be described. - The primary circuit Pc1 receives a low-voltage alternating current, and supplies a high-frequency alternating current to the primary winding P of the transformer TF. The secondary circuit Sc rectifies an alternating current induced in the secondary winding S1 of the transformer TF, and generates a direct current of 24 V. The primary circuit Pc2 rectifies an alternating current induced in the primary winding P3 of the transformer TF, and generates a power supply voltage for the control circuit Cc for the field-effect transistor FET which is described below.
- The primary circuits Pc1 and Pc2, the secondary circuit Sc, and the transformer TF are formed on the
power supply substrate 71. - The primary circuit Pc1 will be described.
- The primary circuit Pc1 is formed by using pattern conductors M1, M2, M3, M4, and M5 of the
power supply substrate 71. The primary circuit Pc1 includes the diode bridge DB disposed among the pattern conductors M1, M2, M3, and M4. The primary circuit Pc1 also includes the capacitor C1 disposed between the pattern conductors M3 and M4. The primary circuit Pc1 also includes the field-effect transistor FET that serves as a switching device and that is disposed between the pattern conductors M4 and M5. - The pattern conductors M1 and M2 receive an alternating current of 100 V from a commercial power supply. The pattern conductors M1 and M2 are terminals that receive alternating current. The diode bridge DB rectifies the received alternating current, and a pulsating current is output to the pattern conductors M3 and M4. The pulsating current that is output to the pattern conductors M3 and M4 is a pulsating current obtained through full-wave rectification. The capacitor C1 smooths the pulsating current obtained from the diode bridge DB. The field-effect transistor FET switches the direct current obtained through smoothing performed by the capacitor C1. A high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M3 and M5.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 and the winding P2 are connected to each other in parallel and the primary winding P is connected to the pattern conductor M3 and the pattern conductor M5.
- The pattern conductor M3 extends so that the pin #1 (end portion P11) of the transformer TF is connected to the pin #3 (end portion P21) of the transformer TF. The pattern conductor M5 connects the pin #2 (end portion P12) of the transformer TF to the pin #4 (end portion P22) of the transformer TF. That is, in the primary winding P, the pattern conductor M3 connects the end portion P11 of the winding P1 to the end portion P21 of the winding P2, and the pattern conductor M5 connects the end portion P12 of the winding P1 to the end portion P22 of the winding P2. In this manner, the winding P1 is connected to the winding P2 in parallel (see
FIG. 3A ). In this case, it is necessary to connect the end portion P11 to the end portion P21 and connect the end portion P12 to the end portion P22. However, the end portion P12 is present between the end portion P11 and the end portion P21, and the end portion P21 is present between the end portion P12 and the end portion P22. Therefore, it is necessary for one of the pattern conductor M3 and the pattern conductor M5 to extend on the secondary circuit Sc side of thepins # 1 to #7. Therefore, in the first exemplary embodiment, in thepower supply unit 70 of the low-voltage system (100 V) illustrated inFIG. 3A , the distance d1 between the pattern conductor M3 of the primary circuit Pc1 and a pattern conductor M31 of the secondary circuit Sc is shorter than the distance d2 between pattern conductors M6, M7, and M8 of the primary circuit Pc1 and pattern conductors M31 and M32 of the secondary circuit Sc in thepower supply unit 70 of the high-voltage system (200 V) illustrated inFIG. 3B . - One end (the end portion P11 and the end portion P21) of the parallel connection between the winding P1 and the winding P2 is connected to the pattern conductor M3, and the other end (the end portion P12 and the end portion P22) is connected to the pattern conductor M5.
- The high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in parallel in the primary winding P, which induces a high-frequency alternating current to the primary winding P3 and the secondary winding S1.
- The secondary circuit Sc will be described.
- The secondary circuit Sc is formed by using pattern conductors M31, M32, and M33 of the
power supply substrate 71. The secondary circuit Sc includes the diode D2 disposed between the pattern conductors M32 and M33. The secondary circuit Sc also includes the capacitor C2 disposed between the pattern conductors M31 and M33. - The secondary winding S1 induces a high-frequency alternating current in the pattern conductors M31 and M32. Then, the high-frequency alternating current is rectified by the diode D2, and is converted into a pulsating current. The pulsating current obtained through rectification performed by the diode D2 is a pulsating current obtained through half-wave rectification. The pulsating current obtained through rectification performed by the diode D2 is smoothed by the capacitor C2. The smoothed direct current is output from the pattern conductors M31 and M33. The pattern conductors M31 and M33 are terminals that output a direct current of 24 V.
- The primary circuit Pc2 will be described.
- The primary circuit Pc2 is formed by using pattern conductors M41, M42, and M43 of the
power supply substrate 71. The primary circuit Pc2 includes the diode D3 disposed between the pattern conductors M42 and M43. The primary circuit Pc2 also includes the capacitor C3 disposed between the pattern conductors M41 and M43. - The primary winding P3 induces a high-frequency alternating current in the pattern conductors M41 and M42. Then, the high-frequency alternating current is rectified by the diode D3, and is converted into a pulsating current. The pulsating current obtained through rectification performed by the diode D3 is a pulsating current obtained through half-wave rectification. The capacitor C3 smooths the pulsating current obtained through rectification performed by the diode D3. The smoothed direct current is output from the pattern conductors M41 and M43. The pattern conductors M41 and M43 are terminals that output a voltage supplied to a control circuit Cc for the field-effect transistor FET, and outputs, for example, a direct current of 20 V.
- The control circuit Cc generates a signal for switching the field-effect transistor FET, and controls the field-effect transistor FET.
- As described above, in the
power supply unit 70 of the low-voltage system (in this example, 100 V), the winding P1 and the winding P2 in the primary winding P are connected to each other in parallel. - By using
FIG. 3B , the primary circuits Pc1 and Pc2 and the secondary circuit Sc in the high-voltage system (200 V) will be described. The primary circuit Pc2 and the secondary circuit Sc are the same as those in thepower supply unit 70 of the low-voltage system (100 V), and will not be described. - The primary circuit Pc1 is formed by using the pattern conductors M1, M2, M4, M6, M7, and M8 of the
power supply substrate 71. The pattern conductors M1, M2, and M4 are the same as those in the low-voltage system inFIG. 3A . The primary circuit Pc1 includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M6. The primary circuit Pc1 also includes the capacitor C1 disposed between the pattern conductors M4 and M6. The primary circuit Pc1 also includes the field-effect transistor FET disposed between the pattern conductors M4 and M7. - The pattern conductors M1 and M2 receive an alternating current of 200 V from a commercial power supply. The pattern conductors M1 and M2 are terminals that receive alternating current. Then, the diode bridge DB rectifies the received alternating current, and a pulsating current is output to the pattern conductors M4 and M6. The capacitor C1 smooths the pulsating current obtained from the diode bridge DB. The field-effect transistor FET switches the direct current obtained through smoothing performed by the capacitor C1. The high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M6 and M7.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in series and the primary winding P is connected to the pattern conductor M6 and the pattern conductor M7.
- The pattern conductor M6 extends so as to be connected to the pin #1 (end portion P11) of the transformer TF. The pattern conductor M7 is connected to the pin #4 (end portion P22) of the transformer TF. The pattern conductor M8 connects the pin #2 (end portion P12) of the transformer TF to the pin #3 (end portion P21) of the transformer TF. That is, in the primary winding P, the pattern conductor M8 connects the end portion P12 of the winding P1 to the end portion P21 of the winding P2. In this manner, the winding P1 is connected to the winding P2 in series (see
FIG. 2B ). - One end (the end portion P11 of the winding P1) of the series connection between the winding P1 and the winding P2 is connected to the pattern conductor M6, and the other end (the end portion P22 of the winding P2) is connected to the pattern conductor M7.
- Accordingly, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current in the secondary winding S1.
- As described above, many components included in the transformer TF are commonly used in the low-voltage
power supply unit 70 and the high-voltagepower supply unit 70. Connection between the winding P1 and the winding P2 (parallel connection or series connection) is set by using the pattern conductors M disposed on thepower supply substrate 71. That is, thepower supply substrate 71 having the pattern conductors M that are different in the low-voltagepower supply unit 70 and in the high-voltagepower supply unit 70 is prepared, achieving common use of many components included in the transformer TF. - In the first exemplary embodiment, the
power supply substrate 71 having the pattern conductors M that are different in the low-voltage system and the high-voltage system is used. - In a second exemplary embodiment, the
power supply substrate 71 having the pattern conductors M that are the same in the low-voltage system and the high-voltage system is used. That is, in the second exemplary embodiment, thepower supply substrate 71 and many components included in the transformer TF are commonly used in the low-voltage system and the high-voltage system. -
FIGS. 4A and 4B illustrate exemplary configurations of thepower supply unit 70 to which the second exemplary embodiment is applied.FIG. 4A illustrates a low-voltagepower supply unit 70, andFIG. 4B illustrates a high-voltagepower supply unit 70. A description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and the high-voltage system is a system for alternating current of 200 V. Components that are substantially identical to components of thepower supply unit 70 to which the first exemplary embodiment is applied are designated with identical reference characters, and will not be described. The transformer TF is substantially the same as the transformer TF in the first exemplary embodiment. The primary circuit Pc2 and the secondary circuit Sc are substantially the same as the primary circuit Pc2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc1 which is different from the primary circuit Pc1 in the first exemplary embodiment will be described. - By using
FIG. 4A , the primary circuit Pc1 in thepower supply unit 70 of the low-voltage system (100 V) will be described. - The primary circuit Pc1 is formed by using pattern conductors M1, M2, M4, M9, M10, M11, and M12 of the
power supply substrate 71. The primary circuit Pc1 includes connection members J1 and J2. The primary circuit Pc1 also includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M9. The primary circuit Pc1 also includes the capacitor C1 disposed between the pattern conductors M4 and M9. The primary circuit Pc1 also includes the field-effect transistor FET disposed between the pattern conductors M4 and M10. - The connection members J1 and J2 are, for example, shorting bars that are members formed of a metallic material which is electrically conductive and that are inserted into two holes provided in advance in the
power supply substrate 71 so as to electrically connect the holes to each other. The connection members J1 and J2 may be jumper wires. Further, the connection members J1 and J2 may be members that are formed as a filter having inductance (L) and resistance (R) and that suppress propagation (passing) of high-frequency noise generated in accordance with the on/off state of the field-effect transistor FET. The same is true for other connection members J described below. - Operations performed by the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M9 and M10.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in parallel and the primary winding P is connected to the pattern conductor M9 and the pattern conductor M10.
- The pattern conductor M9 extends so as to be connected to the pin #1 (end portion P11) of the transformer TF. The pattern conductor M10 extends so as to be connected to the pin #4 (end portion P22) of the transformer TF. The pattern conductor M11 is connected to the pin #2 (end portion P12) of the transformer TF. The pattern conductor M12 is connected to the pin #3 (end portion P21) of the transformer TF.
- The connection member J1 connects the pattern conductor M9 (end portion P11) to the pattern conductor M12 (end portion P21). The connection member J2 connects the pattern conductor M10 (end portion P22) to the pattern conductor M11 (end portion P12).
- That is, in the primary winding P, the connection member J1 connects the end portion P11 of the winding P1 to the end portion P21 of the winding P2, and the connection member J2 connects the end portion P12 of the winding P1 to the end portion P22 of the winding P2. Thus, the winding P1 is connected to the winding P2 in parallel (see
FIG. 2A ). - One end (the end portion P11 and the end portion P21) of the parallel connection between the winding P1 and the winding P2 is connected to the pattern conductor M9, and the other end (the end portion P12 and the end portion P22) is connected to the pattern conductor M10.
- The high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 in the primary winding P that are connected to each other in parallel, which induces a high-frequency alternating current to the secondary winding S1.
- In
FIG. 4A , the connection member J1 underlies the transformer TF. In this case, before the transformer TF is mounted, the connection member J1 may be mounted on thepower supply substrate 71. - By using
FIG. 4B , the primary circuit Pc1 in thepower supply unit 70 of the high-voltage system (200 V) will be described. - The primary circuit Pc1 includes a connection member J3 instead of the connection members J1 and J2 in the
power supply unit 70 of the low-voltage system (100 V) illustrated inFIG. 4A . The other components are substantially the same as components of thepower supply unit 70 of the low-voltage system (100 V), and will not be described. - Similarly to the description about the first exemplary embodiment, in the
power supply unit 70 of the high-voltage system (200 V), the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M9 and M10. - Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in series and the primary winding P is connected to the pattern conductor M9 and the pattern conductor M10.
- The connection member J3 connects the pattern conductor M11 (end portion P12) to the pattern conductor M12 (end portion P21).
- Thus, the end portion P12 of the winding P1 is connected to the end portion P21 of the winding P2 in the primary winding P, and the winding P1 is connected to the winding P2 in series (see
FIG. 2B ). - One end (end portion P11) of the series connection between the winding P1 and the winding P2 is connected to the pattern conductor M9, and the other end (end portion P22) is connected to the pattern conductor M10.
- Accordingly, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S1.
- As described above, in the second exemplary embodiment, the
power supply substrate 71 and many components included in the transformer TF are commonly used in the low-voltagepower supply unit 70 and the high-voltagepower supply unit 70. The connection members J1, J2, and J3 are used to set a connection relationship (parallel connection or series connection) between the winding P1 and the winding P2 in the primary winding P. In the second exemplary embodiment, thepower supply substrate 71 is easily managed. - In the first exemplary embodiment, the distance d1 between the pattern conductor M3 of the primary circuit Pc1 and the pattern conductor M31 of the secondary circuit Sc in the
power supply unit 70 of the low-voltage system (100 V) illustrated inFIG. 3A is shorter than the distance d2 between the pattern conductors M6, M7, and M8 of the primary circuit Pc1 and the pattern conductors M31 and M32 of the secondary circuit Sc in thepower supply unit 70 of the high-voltage system (200 V) illustrated inFIG. 3B . - Also in the second exemplary embodiment, as illustrated in
FIGS. 4A and 4B , when the distance between thepin # 1 and thepin # 14 is the same in the first exemplary embodiment and the second exemplary embodiment, the distance d3 between the pattern conductors M9 and M12 of the primary circuit Pc1 and the pattern conductor M31 of the secondary circuit Sc is shorter than the distance d2 in thepower supply unit 70 of the high-voltage system (200 V) according to the first exemplary embodiment illustrated inFIG. 3B . Therefore, the electric field in this portion is high. - Therefore, in the third exemplary embodiment, in both of the
power supply unit 70 of the low-voltage system (100 V) and thepower supply unit 70 of the high-voltage system (200 V), the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2. Since the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is determined according to a safety standard, it is necessary to keep a necessary and sufficient distance. Accordingly, if the distance d1 and the distance d3 are equal to the distance d2, the size of the apparatus is increased. -
FIGS. 5A and 5B illustrate exemplary configurations of thepower supply unit 70 to which a third exemplary embodiment is applied.FIG. 5A illustrates a low-voltagepower supply unit 70, andFIG. 5B illustrates a high-voltagepower supply unit 70. A description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V, and the high-voltage system is a system for alternating current of 200 V. Components substantially identical to components inpower supply unit 70 to which the first exemplary embodiment and the second exemplary embodiment are applied are designated with identical reference characters, and will not be described. The transformer TF is substantially the same as the transformer TF in the first exemplary embodiment. The primary circuit Pc2 and the secondary circuit Sc are substantially the same as the primary circuit Pc2 and the secondary circuit Sc in the first exemplary embodiment. The primary circuit Pc1 that is different from the primary circuit Pc1 in the first exemplary embodiment will be described. - By using
FIG. 5A , the primary circuit Pc1 in thepower supply unit 70 of the low-voltage system (100 V) will be described. - The primary circuit Pc1 is formed by using pattern conductors M1, M2, M4, M13, M14, and M15 of the
power supply substrate 71. The primary circuit Pc1 includes a connection member J4. The primary circuit Pc1 also includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M13. The primary circuit Pc1 also includes the capacitor C1 disposed between the pattern conductors M4 and M13. The primary circuit Pc1 also includes the field-effect transistor FET disposed between the pattern conductors M4 and M14. - Operations performed by the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M13 and M14.
- Any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in parallel and the primary winding P is connected to the pattern conductors M13 and M14.
- The pattern conductor M13 extends so as to be connected to the pin #1 (end portion P11) of the transformer TF. The pattern conductor M14 is disposed so as to connect the pin #2 (end portion P12) of the transformer TF to the pin #4 (end portion P22) of the transformer TF. The pattern conductor M15 is connected to the pin #3 (end portion P21) of the transformer TF.
- The connection member J4 connects the pattern conductor M13 (end portion P11) to the pattern conductor M15 (end portion P21).
- That is, in the primary winding P, the connection member J4 connects the end portion P11 of the winding P1 to the end portion P21 of the winding P2, and the pattern conductor M14 connects the end portion P12 of the winding P1 to the end portion P22 of the winding P2. The pattern conductor M14 is disposed so as to detour around the pattern conductor M15 on the primary circuit Pc side, and connects the end portion P12 to the end portion P22. Thus, the winding P1 is connected to the winding P2 in parallel (see
FIG. 2A ). The pattern conductor M14 may be called a connection pattern conductor. - One end (the end portion P11 and the end portion P21) of the parallel connection between the winding P1 and the winding P2 is connected to the pattern conductor M13, and the other end (the end portion P12 and the end portion P22) is connected to the pattern conductor M14.
- Therefore, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected in parallel in the primary winding P, which induces a high-frequency alternating current to the secondary winding S1.
- As illustrated in
FIG. 5A , the connection member J4 connects the pin #1 (end portion P11) of the transformer TF to the pin #3 (end portion P21) of the transformer TF, and the pattern conductor M14 connects the pin #2 (end portion P12) to the pin #4 (end portion P22). Thus, the distance between the pattern conductors M13, M14, and M15 of the primary circuit Pc1 and the pattern conductor M31 of the secondary circuit Sc is set to the distance d2. - The primary circuit Pc1 in the
power supply unit 70 of the high-voltage system (200 V) illustrated inFIG. 5B is the same as that in thepower supply unit 70 of the high-voltage system (200 V) in the first exemplary embodiment illustrated inFIG. 3B . As described above, the distance between the pattern conductors M6, M7, and M8 of the primary circuit Pc1 and the pattern conductors M31 and M32 of the secondary circuit Sc in thepower supply unit 70 of the high-voltage system (200 V) illustrated inFIG. 3B is set to the distance d2. - The
power supply unit 70 to which a fourth exemplary embodiment is applied is smaller than thepower supply units 70 in the first to third exemplary embodiments. That is, the size of thepower supply substrate 71 is smaller. - For example, in the
power supply unit 70 according to the first exemplary embodiment, in connection between the end portion P12 and the end portion P22 in the low-voltagepower supply unit 70 illustrated inFIG. 3A , the end portion P21 is interposed between the end portion P12 and the end portion P22. Therefore, the pattern conductor M5 is provided. Accordingly, when thepower supply substrate 71 having the same size is used, a region a (a region surrounded by the pattern conductors M4, M6, M7, and M8) is not used in the high-voltagepower supply unit 70 illustrated inFIG. 3B , resulting in an increase in the size of thepower supply substrate 71. - In the
power supply unit 70 according to the third exemplary embodiment, in connection between the end portion P12 and the end portion P22 in the low-voltagepower supply unit 70 illustrated inFIG. 5A , the end portion P21 is interposed between the end portion P12 and the end portion P22. Therefore, the pattern conductor M14 is provided. Accordingly, the region a (the region surrounded by the pattern conductors M4, M6, M7, and M8) illustrated inFIG. 5B is not used, resulting in an increase in the size of thepower supply substrate 71. -
FIGS. 6A and 6B illustrate exemplary configurations of thepower supply unit 70 to which the fourth exemplary embodiment is applied.FIG. 6A illustrates a low-voltagepower supply unit 70, andFIG. 6B illustrates a high-voltagepower supply unit 70. A description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and that the high-voltage system is a system for alternating current of 200 V. Components substantially identical to components in the first exemplary embodiment are designated with identical reference characters, and will not be described. - The transformer TF will be described. As described above, the transformer TF is commonly used in the low-voltage power supply unit 70 (
FIG. 6A ) and the high-voltage power supply unit 70 (FIG. 6B ). - The number and arrangement of pins (
pins # 1 to #14) of the transformer TF are the same as the number and arrangement in the first exemplary embodiment. - Similarly to the first and third exemplary embodiments, the transformer TF includes the primary winding P (windings P1 and P2) and the secondary winding S1. The connection relationship indicating how pins are connected to the windings P1 and P2 in the fourth exemplary embodiment is different from the connection relationship in the first and third exemplary embodiments.
- In the winding P1, the end portion P11 is connected to the
pin # 1, and the end portion P12 is connected to thepin # 3. In the winding P2, the end portion P21 is connected to thepin # 2, and the end portion P22 is connected to thepin # 4. - The winding S1 and the winding P3 are substantially the same as the winding S1 and the winding P3 in the first exemplary embodiment, and will not be described.
- Nothing is connected to the
pins # 5 and #11. - The primary circuit Pc2 and the secondary circuit Sc are substantially the same as the primary circuit Pc2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc1 will be described.
- By using
FIG. 6A , the primary circuit Pc1 in thepower supply unit 70 of the low-voltage system (100 V) will be described. - The primary circuit Pc1 is formed by using pattern conductors M1, M2, M4, M20, and M21 of the
power supply substrate 71. The primary circuit Pc1 includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M20. The primary circuit Pc1 includes the capacitor C1 disposed between the pattern conductors M4 and M20. The primary circuit Pc1 includes the field-effect transistor FET disposed between the pattern conductors M4 and M21. - Operation of the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M20 and M21.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in parallel and the primary winding P is connected to the pattern conductors M20 and M21.
- The pattern conductor M20 extends so as to be connected to the pin #1 (end portion P11) and the pin #2 (end portion P21) of the transformer TF. The pattern conductor M21 is disposed so as to connect the pin #3 (end portion P12) of the transformer TF to the pin #4 (end portion P22) of the transformer TF.
- That is, the pattern conductor M20 connects the end portion P11 of the winding P1 to the end portion P21 of the winding P2 in the primary winding P, and the pattern conductor M21 connects the end portion P12 of the winding P1 and the end portion P22 of the winding P2. Thus, the winding P1 is connected to the winding P2 in parallel (see
FIG. 2A ). - One end (the end portion P11 and the end portion P21) of the parallel connection between the winding P1 and the winding P2 is connected to the pattern conductor M20, and the other end (the end portion P12 and the end portion P22) is connected to the pattern conductor M21.
- The connection relationship of pins in the winding P1 is different from the connection relationship in the winding P2. Thus, the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2.
- As described above, in the third exemplary embodiment, the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc in the
power supply unit 70 of the low-voltage system (100 V) illustrated inFIG. 5A is set to the distance d2. In the parallel connection between the winding P1 and the winding P2 in the primary winding P, connection is made by using the connection member J4 at one end (the end portion P11 and the end portion P21), and connection is made by using the pattern conductor M14 at the other end (the end portion P12 and the end portion P22). That is, electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced). - In contrast, in the
power supply unit 70 according to the fourth exemplary embodiment, as illustrated inFIG. 6A , connection is made by using the pattern conductor M20 at one end (the end portion P11 and the end portion P21), and connection is made by using the pattern conductor M21 at the other end (the end portion P12 and the end portion P22). Thus, electric characteristics at one end of the primary winding P and electric characteristics at the other end are not asymmetrical (balanced). - By using
FIG. 6B , the primary circuit Pc1 in thepower supply unit 70 of the high-voltage system (200 V) will be described. - The primary circuit Pc1 is formed by using pattern conductors M1, M2, M4, M22, M23, and M24 of the
power supply substrate 71. The primary circuit Pc1 includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M22. The primary circuit Pc1 includes the capacitor C1 disposed between the pattern conductors M4 and M22. The primary circuit Pc1 includes the field-effect transistor FET disposed between the pattern conductors M4 and M24. - Operations performed by the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M22 and M24.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in series and the primary winding P is connected to the pattern conductors M22 and M24.
- The pattern conductor M22 extends so as to be connected to the pin #1 (end portion P11) of the transformer TF. The pattern conductor M23 is disposed so as to connect the pin #2 (end portion P21) of the transformer TF to the pin #3 (end portion P12) of the transformer TF. The pattern conductor M24 is disposed so as to be connected to the pin #4 (end portion P22) of the transformer TF.
- That is, the pattern conductor M23 connects the end portion P12 of the winding P1 to the end portion P21 of the winding P2 in the primary winding P. Thus, the winding P1 is connected to the winding P2 in series (see
FIG. 2B ). - One end (end portion P11) of the series connection between the winding P1 and the winding P2 is connected to the pattern conductor M22, and the other end (end portion P22) is connected to the pattern conductor M24.
- Accordingly, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S1.
- The connection relationship of pins in the winding P1 is different from the connection relationship in the winding P2 so that the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2.
- A region surrounded by the pattern conductors M4, M22, M23, and M24 is smaller than the regions a illustrated in
FIGS. 3B and 5B . - As described above, in the fourth exemplary embodiment, the connection relationship indicating how pins are connected to the windings P1 and P2 of the primary winding P in the transformer TF is different from the connection relationship in the first exemplary embodiment. Thus, many components included in the transformer TF are commonly used, and the size of the
power supply substrate 71 is smaller than the size in the first exemplary embodiment. - In the low-voltage
power supply unit 70 and the high-voltagepower supply unit 70, the distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2. - In addition, in the low-voltage
power supply unit 70, the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical is avoided. - Further, in the high-voltage system, the state in which pins (pattern conductors M) that produce a large potential difference are disposed adjacent to each other is avoided.
- Furthermore, the shapes of pattern conductors M of the
power supply substrate 71 of the low-voltagepower supply unit 70 are different from the shapes for the high-voltagepower supply unit 70. However, a connection member J does not need to be used. - Moreover, in both of the low-voltage system and the high-voltage system, the end portions connecting the winding P1 of the transformer TF to the winding P2 are disposed adjacent to each other.
- The
power supply unit 70 to which the fourth exemplary embodiment is applied uses thepower supply substrate 71 on which different pattern conductors M are used in the low-voltagepower supply unit 70 and the high-voltagepower supply unit 70. - The
power supply unit 70 to which a fifth exemplary embodiment is applied uses thepower supply substrates 71 on which the same pattern conductors M are used in the low-voltagepower supply unit 70 and the high-voltagepower supply unit 70. -
FIGS. 7A and 7B illustrate exemplary configurations of thepower supply unit 70 to which the fifth exemplary embodiment is applied.FIG. 7A illustrates a low-voltagepower supply unit 70, andFIG. 7B illustrates a high-voltagepower supply unit 70. A description will be made under the assumption that the low-voltage system is a system for alternating current of 100 V and that the high-voltage system is a system for alternating current of 200 V. Components substantially identical to components in the first exemplary embodiment are designated with identical reference characters, and will not be described. - The transformer TF is substantially the same as the transformer TF in the fourth exemplary embodiment, and will not be described.
- The primary circuit Pc2 and the secondary circuit Sc are substantially the same as the primary circuit Pc2 and the secondary circuit Sc in the first exemplary embodiment. Accordingly, the primary circuit Pc1 that is different from the primary circuit Pc1 in the first exemplary embodiment will be described.
- By using
FIG. 7A , the primary circuit Pc1 in thepower supply unit 70 of the low-voltage system (100 V) will be described. - The primary circuit Pc1 is formed by using pattern conductors M1, M2, M4, M25, M26, M27, and M28 of the
power supply substrate 71. The primary circuit Pc1 includes connection members J5 and J6. The primary circuit Pc1 also includes the diode bridge DB disposed among the pattern conductors M1, M2, M4, and M25. The primary circuit Pc1 also includes the capacitor C1 disposed between the pattern conductors M4 and M25. The primary circuit Pc1 also includes the field-effect transistor FET disposed between the pattern conductors M4 and M28. - Operations performed by the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M25 and M28.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in parallel and the primary winding P is connected to the pattern conductors M25 and M28.
- The pattern conductor M25 extends so as to be connected to the pin #1 (end portion P11) of the transformer TF. The pattern conductor M26 is connected to the pin #2 (end portion P21) of the transformer TF. The pattern conductor M27 is connected to the pin #3 (end portion P12) of the transformer TF. The pattern conductor M28 is connected to the pin #4 (end portion P22) of the transformer TF.
- The connection member J5 connects the pattern conductor M25 to the pattern conductor M26, and the connection member J6 connects the pattern conductor M27 to the pattern conductor M28.
- That is, the connection member J5 connects the end portion P11 of the winding P1 to the end portion P21 of the winding P2 in the primary winding P, and the connection member J6 connects the end portion P12 of the winding P1 to the end portion P22 of the winding P2. Thus, the winding P1 is connected to the winding P2 in parallel (see
FIG. 2A ). - One end (the end portion P11 and the end portion P21) of the parallel connection between the winding P1 and the winding P2 is connected to the pattern conductor M25, and the other end (the end portion P12 and the end portion P22) is connected to the pattern conductor M28.
- Accordingly, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in parallel in the primary winding P, which induces a high-frequency alternating current to the secondary winding S1.
- The distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2.
- Connection is made by using the connection member J5 at one end (the end portion P11 and the end portion P21) of the primary winding P, and connection is made by using the connection member J6 at the other end (the end portion P12 and the end portion P22). Accordingly, the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced) is avoided.
- A setting is made so that the difference in impedance between the connection member J5 and the connection member J6 is reduced. Thus, the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical (unbalanced) is further avoided.
- By using
FIG. 7B , the primary circuit Pc1 in thepower supply unit 70 of the high-voltage system (200 V) will be described. - The pattern conductors M1, M2, M4, M25, M26, M27, and M28 of the
power supply substrate 71 of the primary circuit Pc1 are substantially the same as the pattern conductors M1, M2, M4, M25, M26, M27, and M28 of thepower supply unit 70 of the low-voltage system (100 V) inFIG. 7A . The connection relationships of the diode bridge DB, the capacitor C1, and the field-effect transistor FET are the same as the connection relationships inFIG. 7A . - The primary circuit Pc1 includes a connection member J7 instead of the connection members J5 and J6 of the
power supply unit 70 of the low-voltage system (100 V) inFIG. 7A . - Operations performed by the primary circuit Pc1 are the same as the operations in the first exemplary embodiment. That is, the high-frequency alternating current generated through switching using the field-effect transistor FET is output to the pattern conductors M25 and M28.
- Accordingly, any configuration of the primary winding P may be employed as long as the winding P1 is connected to the winding P2 in series and the primary winding P is connected to the pattern conductors M25 and M28.
- The connection member J7 connects the pattern conductor M26 to the pattern conductor M27.
- That is, the connection member J7 connects the end portion P12 of the winding P1 to the end portion P21 of the winding P2 in the primary winding P. Thus, the winding P1 is connected to the winding P2 in series (see
FIG. 2B ). - One end (end portion P11) of the winding P in which series connection is made is connected to the pattern conductor M25, and the other end (end portion P22) is connected to the pattern conductor M28.
- Accordingly, the high-frequency alternating current generated through switching using the field-effect transistor FET flows through the winding P1 and the winding P2 that are connected to each other in series in the primary winding P, which induces a high-frequency alternating current to the secondary winding S1.
- Similarly to the fourth exemplary embodiment, in the
power supply unit 70 of the high-voltage system (200 V) according to the fifth exemplary embodiment, the pin #1 (end portion P11) and the pin #4 (end portion P22) between which the potential difference is the largest are disposed apart with the pin #2 (end portion P21) and the pin #3 (end portion P12) that are at a midpoint potential and that are interposed between thepin # 1 and thepin # 4. Accordingly, a high electric field is unlikely to be produced between the pins and between the pattern conductors M connected to the pins. - As described above, in the fifth exemplary embodiment, many components included in the transformer TF are commonly used in the low-voltage
power supply unit 70 and the high-voltagepower supply unit 70. Thepower supply substrate 71 is also commonly used. Setting of the low-voltagepower supply unit 70 and the high-voltagepower supply unit 70 is made by using the connection members J. - The distance between the pattern conductors M of the primary circuit Pc1 and the pattern conductors M of the secondary circuit Sc is set to the distance d2 in the low-voltage
power supply unit 70 and the high-voltagepower supply unit 70. - In the low-voltage system, the state in which electric characteristics at one end of the primary winding P and electric characteristics at the other end are asymmetrical is avoided.
- Further, in the high-voltage system, the state in which pins (pattern conductors M) between which the potential difference is large are disposed adjacent to each other is avoided.
- Furthermore, in both of the low-voltage system and the high-voltage system, the end portions connecting the winding P1 and the winding P2 of the transformer TF are disposed adjacent to each other. The connecting end portions of the transformer TF are disposed adjacent to each other.
- In the first to fifth exemplary embodiments, the state in which the winding P1 and the winding P2 are disposed in parallel in the primary winding P is described. The winding P1 and the winding P2 may be provided in any winding manner such as overlap winding. Any configuration may be employed as long as the terminals of the winding P1 and the winding P2 in the primary winding P are arranged as described in the first to fifth exemplary embodiments.
- Various combinations and changes may be made without departing from the gist of the present invention.
Claims (19)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2016250150A JP2018107866A (en) | 2016-12-22 | 2016-12-22 | Power supply device, image forming apparatus and transformer |
JP2016-250150 | 2016-12-22 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20180183341A1 true US20180183341A1 (en) | 2018-06-28 |
US10554131B2 US10554131B2 (en) | 2020-02-04 |
Family
ID=62630211
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/583,391 Active US10554131B2 (en) | 2016-12-22 | 2017-05-01 | Power supply unit having a transformer with a primary winding and a secondary winding for supplying a voltage |
Country Status (3)
Country | Link |
---|---|
US (1) | US10554131B2 (en) |
JP (1) | JP2018107866A (en) |
CN (1) | CN108233717B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN215010075U (en) * | 2021-03-09 | 2021-12-03 | 西安特锐德智能充电科技有限公司 | High-voltage output switching circuit |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5781071A (en) * | 1994-12-17 | 1998-07-14 | Sony Corporation | Transformers and amplifiers |
US6531998B1 (en) * | 2000-02-29 | 2003-03-11 | Microsoft Corporation | Haptic feedback gaming device with integral power supply |
US20080258703A1 (en) * | 2005-12-30 | 2008-10-23 | Creative Technology Ltd | Power Supply With Reduced Power Losses During Standby Mode |
US20110222319A1 (en) * | 2010-03-09 | 2011-09-15 | Omron Corporation | Switching power supply |
US20140346867A1 (en) * | 2011-09-06 | 2014-11-27 | Whirlpool S.A. | Home appliance comprising an electric motor having at least two coils, method and system for controlling the home appliance, use of electric motor for feeding in the home appliance |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3348654B2 (en) * | 1998-07-17 | 2002-11-20 | 日本電気株式会社 | Transformation circuit |
JP2000350454A (en) * | 1999-06-04 | 2000-12-15 | Seiko Epson Corp | Switching power supply unit and voltage control thereof |
CN101326598B (en) * | 2005-12-16 | 2011-07-27 | 株式会社村田制作所 | Composite transformer and insulated switching power supply |
CN100527581C (en) * | 2006-02-02 | 2009-08-12 | 索尼株式会社 | Switching power supply circuit |
JP4525617B2 (en) * | 2006-03-03 | 2010-08-18 | ソニー株式会社 | Switching power supply circuit |
JP4966249B2 (en) * | 2008-05-07 | 2012-07-04 | コーセル株式会社 | Switching power supply |
JP2012023933A (en) * | 2010-07-16 | 2012-02-02 | Fuji Xerox Co Ltd | Power supply device, and image formation device |
JP5504219B2 (en) * | 2011-07-27 | 2014-05-28 | 日立オートモティブシステムズ株式会社 | Power converter |
JP3180974U (en) * | 2012-11-01 | 2013-01-17 | 株式会社豊田自動織機 | DC-DC converter |
JP6077383B2 (en) * | 2013-05-09 | 2017-02-08 | 株式会社デンソー | Power converter |
JP6151110B2 (en) * | 2013-07-01 | 2017-06-21 | 株式会社日立製作所 | Power converter |
JP2015109782A (en) | 2013-12-06 | 2015-06-11 | 株式会社三社電機製作所 | Dc-dc converter including pfc circuit |
CN204290730U (en) * | 2014-12-12 | 2015-04-22 | 西南交通大学 | A kind of control device of High Power Factor high efficiency anti exciting converter of discontinuous mode |
-
2016
- 2016-12-22 JP JP2016250150A patent/JP2018107866A/en active Pending
-
2017
- 2017-05-01 US US15/583,391 patent/US10554131B2/en active Active
- 2017-06-07 CN CN201710422534.7A patent/CN108233717B/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5781071A (en) * | 1994-12-17 | 1998-07-14 | Sony Corporation | Transformers and amplifiers |
US6531998B1 (en) * | 2000-02-29 | 2003-03-11 | Microsoft Corporation | Haptic feedback gaming device with integral power supply |
US20080258703A1 (en) * | 2005-12-30 | 2008-10-23 | Creative Technology Ltd | Power Supply With Reduced Power Losses During Standby Mode |
US20110222319A1 (en) * | 2010-03-09 | 2011-09-15 | Omron Corporation | Switching power supply |
US20140346867A1 (en) * | 2011-09-06 | 2014-11-27 | Whirlpool S.A. | Home appliance comprising an electric motor having at least two coils, method and system for controlling the home appliance, use of electric motor for feeding in the home appliance |
Also Published As
Publication number | Publication date |
---|---|
CN108233717A (en) | 2018-06-29 |
US10554131B2 (en) | 2020-02-04 |
CN108233717B (en) | 2021-05-18 |
JP2018107866A (en) | 2018-07-05 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10842019B2 (en) | Printed circuit board and image forming apparatus | |
US9665060B2 (en) | Power supply apparatus, image forming apparatus, and noise filter | |
US8717605B2 (en) | Image forming apparatus and circuit board of image forming apparatus | |
JP2006311787A (en) | Power supply device and image forming apparatus equipped with power supply device | |
US20230341798A1 (en) | Image forming apparatus | |
JP2018005065A (en) | Image forming apparatus and belt unit | |
US10554131B2 (en) | Power supply unit having a transformer with a primary winding and a secondary winding for supplying a voltage | |
JP6548535B2 (en) | Electronic equipment | |
US10732560B2 (en) | Electrical equipment with varistor mounted | |
CN110531593B (en) | Image forming apparatus with a toner supply device | |
CN100476607C (en) | Power supply apparatus, and image forming apparatus having the same | |
US9164477B2 (en) | Current leakage correction in humid environments | |
US10152010B2 (en) | Signal transmitting apparatus and image forming apparatus | |
JP2014077982A (en) | Transfer device and image forming apparatus | |
JP2002158408A (en) | Printed board and image forming device | |
JP2021069254A (en) | Power supply device and image forming apparatus | |
JP2006059875A (en) | High voltage power supply unit used for image forming device | |
JP7303646B2 (en) | Power supply and image forming device | |
US10983464B2 (en) | Image heating device with first and second groups of conductors having different widths, and image forming apparatus | |
JP4497662B2 (en) | Component mounting board | |
US9459582B2 (en) | Image forming apparatus including voltage and current application lines | |
US20230209699A1 (en) | Humidity-adjusted power supply | |
JP5386816B2 (en) | Power supply device and image forming apparatus | |
JP2022085405A (en) | Power supply device and image forming apparatus | |
JP2017175081A (en) | Wiring structure and image forming apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FUJI XEROX CO., LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YOSHIDA, TAKAYUKI;MISUMI, HAJIME;TAJI, TSUTOMU;AND OTHERS;REEL/FRAME:042201/0832 Effective date: 20170403 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NOTICE OF ALLOWANCE MAILED -- APPLICATION RECEIVED IN OFFICE OF PUBLICATIONS |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: PUBLICATIONS -- ISSUE FEE PAYMENT RECEIVED |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: FUJIFILM BUSINESS INNOVATION CORP., JAPAN Free format text: CHANGE OF NAME;ASSIGNOR:FUJI XEROX CO., LTD.;REEL/FRAME:058287/0056 Effective date: 20210401 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 4 |